Absorbent article with elastic feature having a portion mechanically prestrained

ABSTRACT

Absorbent articles having a unique elastic feature improving the dynamic fit as well as containment characteristics. The elastic feature preferably comprises an elastomeric member and a segment of the backsheet; a portion of the backsheet segment coincides with at least a portion of the elastomeric member; this portion of the backsheet segment being mechanically prestrained. Mechanical prestraining of the backsheet segment improves not only the extension of the elastomeric member, but also the heat-shrink contraction of preferred elastomeric members.

This is a continuation of application Ser. No. 07/750,775 filed on Aug.22, 1991, now U.S. Pat. No. 5,151,092; which is a continuation-in-partof application Ser. No. 07/715,152 filed on Jun. 13, 1991, abandoned.

FIELD OF THE INVENTION

The present invention relates to absorbent articles such as diapers,incontinent briefs, diaper holders, and the like, and more particularly,to absorbent articles having elastic waist features providing dynamicfit about the wearer as well as improved containment characteristics ofthe absorbent article.

BACKGROUND OF THE INVENTION

Infants and other incontinent individuals wear absorbent articles suchas diapers to receive and contain urine and other body exudates.Absorbent articles function both to contain the discharged materials andto isolate these materials from the body of the wearer and from thewearer's garments and bed clothing. Disposable absorbent articles havingmany different basic designs are known to the art. For example, U.S.Pat. No. 26,152, entitled "Disposable Diaper" issued to Duncan and Bakeron Jan. 31, 1967, describes a disposable diaper which has achieved wideacceptance and commercial success U.S. Pat. No. 3,860,003, entitled"Contractable Side Portions For Disposable Diaper", issued to Buell onJan. 14, 1975, describes an elasticized leg cuff disposable diaper whichhas achieved wide acceptance and commercial success.

However, absorbent articles have a tendency to sag or gap away from andto slide/slip down on the body of the wearer during wear. Thissagging/gapping and sliding/slipping is caused by the relative motionsof the wearer as the wearer breathes, moves and changes positions, bythe downward forces generated when the absorbent article is loaded withbody exudates, and by the wear. This sagging/gapping andsliding/slipping is caused by the relative motions of the wearer as thewearer breathes, moves and changes positions, by the downward forcesgenerated when the absorbent article is loaded with body exudates, andby the deformation of the materials of the absorbent article itself whensubjected to such wearer's motions. This sagging/gapping andsliding/slipping of the absorbent article can lead to premature leakageand poor fit of the absorbent article about the wearer in the waistregions and the leg regions of the absorbent article.

In order to more snugly fit absorbent articles about the waist of thewearer, certain commercially available absorbent articles have beenprovided with elastic waist features. An example of a disposable diaperwith an elastic waist feature which has achieved wide acceptance andcommercial success is disclosed in U.S. Pat. No. 4,515,595 issued toKievit and Osterhage on May 7, 1985. Elastic waist features willtypically comprise an elasticized waistband consisting of an elasticmember contractibly affixed between the topsheet and the backsheet. Theelasticized waistband is, thus, designed to expand and contract with thewearer's motions and to maintain the fit of the absorbent article aboutthe waist of the wearer during use (i.e., provide sustained dynamicfit).

However, it has been found that absorbent articles having elastic waistfeatures also have a tendency to sag/gap and slide/slip during use.Further, the elastic waist feature has a tendency to rollover or roll-inat the front of the diaper resulting in a lack of fit about the waist ofthe wearer.

Thus, it would be advantageous to provide an absorbent article having anelastic waist feature that provides better fit, reduced leakage, andwearer comfort. It would further be advantageous to provide an absorbentarticle which has reduced sagging, gapping, rollover, or roll-in at thewaist of the diaper as well as reduced overall sliding/slipping of theabsorbent article or the absorbent core on the wearer during use.

Therefore, it is an object of the present invention to provide anabsorbent article having sustained dynamic fit about the waist of thewearer during use.

It is a further object of the present invention to provide an absorbentarticle having a unique elastic waist feature that provides sustaineddynamic fit and improved resistance to leakage during use.

It is a still further object of the present invention to provide anabsorbent article having a unique elastic waist feature which reducessagging, gapping, rollover or roll-in at the front of the diaper as wellas overall sliding/slipping of the absorbent article or the absorbentcore during use.

It is an another object of the present invention to provide a uniqueelastic waist feature having an elasticized waistband that provides suchsustained dynamic fit by providing a predisposed, resilient, waistbandflexural hinge zone which allows relative flexural bending between zonesof the elasticized waistband and provides a restoring force/moment toresiliently return the zones to essentially their preceding in-useconfiguration.

It is a further object of the present invention to provide a closuresystem that maintains/creates lateral tension through at least a portionof the unique elastic waist feature to enhance the sustained dynamicfit.

These and other objects of the present invention will be more readilyapparent when considered in reference to the following description andwhen taken in conjunction with the accompanying drawings.

SUMMARY OF THE INVENTION

The present invention provides absorbent articles such as disposablediapers, incontinent briefs, diaper holders and the like, that have aunique elastic waist feature that improves the dynamic fit of theelasticized waistband as well as the containment characteristics of theabsorbent article. Such absorbent articles comprise a containmentassembly preferably comprising a liquid pervious topsheet, a liquidimpervious backsheet, and an absorbent core positioned between thetopsheet and the backsheet; an elastic waist feature; and a closuresystem for creating/maintaining lateral tension through at least aportion of the elastic waist feature.

The elastic waist feature preferably comprises an interconnecting panelzone, a first flexural hinge zone joining the interconnecting panel zonewith the containment assembly, an elasticized waistband, and a secondflexural hinge zone joining the elasticized waistband with theinterconnecting panel zone. The elasticized waistband comprises ashaping panel zone; a waistline panel zone; and a predisposed,resilient, waistband flexural hinge zone joining the shaping panel zoneand the waistline panel zone. The interconnecting panel zone provides aflexible link between the elasticized waistband and the containmentassembly to allow rotations and translations of the elasticizedwaistband so that the elasticized waistband may move in functionalcontacting position and conform with the waist of the wearer. Theelasticized waistband is designed to elastically expand and contract andto dynamically fit the wearer's waist. The waistband flexural hinge zoneis predisposed to allow the panel zones to flexurally bend about adefined axes or zone and is resilient to provide a restoringforce/moment that returns the panel zones to their preceding in-useconfiguration, especially when the elasticized waistband has beenpretensioned by the closure system. Thus, the elastic waist featuremoves with and conforms to the waist of the wearer as the wearer sits,stands or moves. The elasticized waistband preferably comprises aportion of the topsheet, a portion of the backsheet that is preferablyprestrained, an elastomeric member, and a resilient member that enhancesthe resiliency for the waistband flexural hinge zone.

The absorbent article is also preferably provided with a closure system(tensioning means) for dynamically creating/maintaining lateral tensionthrough the elasticized waistband. The lateral tension dynamicallycreated and maintained by the closure system "activates" the stretch ofthe elasticized waistband thereby allowing it to more dynamically expandand contract with the motions of the wearer. The closure systempreferably comprises a dual tension fastening system. The dual tensionfastening system comprises a primary fastening system for forming a sideclosure and a waist closure system for forming a waist closure. Theprimary fastening system maintains the first waist region and the secondwaist region in an overlapping configuration such that lateral tensionsare maintained around the circumference of the diaper to maintain thediaper on the wearer. The primary fastening system comprises asecurement member, preferably a tape tab and a first fasteningcomponent, and a landing member preferably comprising a second fasteningcomponent to provide a variable positioning side closure. The waistclosure system forms a waist closure that anchors a portion of the endedge of the absorbent article and that dynamically maintains/createslateral tensions through the elasticized waistband so as to improve thefit and containment characteristics of the diaper by reducing gapping,sagging, and rollover of the elasticized waistband. The waist closuresystem comprises at least one, preferably a pair of, first attachmentcomponent(s) longitudinally aligned with the elasticized waistband andat least one second attachment component. Each attachment componentcomprises a fastening means that engages a complementary fastening meansfor providing a variable positioning, passively activated, waistclosure. The first attachment component(s) preferably comprise a hookfastening material while the second attachment component preferablycomprises a loop fastening material.

In an especially preferred embodiment of the present invention, theabsorbent article additionally comprises a pair of elasticized sidepanels disposed in the second waist region. The elasticized side panelsprovide an elastically extensible feature that provides a morecomfortable and contouring fit by initially conformably fitting thediaper to the wearer and by sustaining this fit. The elasticized sidepanels further develop and maintain wearing forces (tensions) thatenhance the tensions developed and maintained by both the primaryfastening system and the waist closure system. The elasticized sidepanels especially assist in pretensioning the elasticized waistband andfurther provide more effective application of the diaper. While eachelasticized side panel may be constructed in a number of configurations,the elasticized side panel preferably comprises a "zero strain" stretchlaminate. The elasticized side panel also preferably has an extensionpanel adjacent the leg of the wearer so that tensional forces throughthe side panel are not concentrated so as to prevent the indentation,rubbing, or chafing of the wearer's skin during use.

The present invention also relates to alternative elastic waist featurescomprising an "expansive tummy panel" elasticized waistband. In theseembodiments the elasticized waistband is capable of expanding wellbeyond the dimensions of the absorbent article set by the primaryfastening system (beyond the planar state of the diaper itself) so as toaccommodate wearers, especially large infants, with large expansilewaists so as to reduce the sagging/slipping of the absorbent article.The extension forces of the elasticized waistband are lower than theextension forces of the elasticized side panels so as to accomodate suchexpansion. In a preferred embodiment of this elastic waist feature, theelasticized waistband is formed from a stretch laminate. The stretchlaminate is comprised of an elastomeric member and a portion of thetopsheet and the backsheet which all have been mechanically stretched.In a preferred embodiment, the waistline panel zone is formed byremoving a portion of the backsheet (windowing). The shape of theelasticized waistband also provides differential extensibility in thelateral direction.

BRIEF DESCRIPTION OF THE DRAWINGS

While the specification concludes with claims particularly pointing outand distinctly claiming the subject matter which is regarded as formingthe present invention, it is believed that the invention will be betterunderstood from the following description which is taken in conjunctionwith the accompanying drawings in which like designations are used todesignate substantially identical elements, and in which:

FIG. 1 is a plan view of a disposable diaper embodiment of the presentinvention having portions cut-away to reveal underlying structure, theouter surface of the diaper facing the viewer;

FIG. 2 is a fragmentary sectional view of the disposable diaper shown inFIG. 1 taken along section line 2--2 of FIG. 1;

FIG. 2A is a plan view of the prestrained backsheet portion of thedisposable diaper showing the pattern of the mechanical stretching;

FIG. 2B is a simplified, fragmentary, enlarged plan view of thedisposable diaper of the present invention in the first waist regionshowing the elements of the elastic waist feature;

FIG. 3 is a fragmentary sectional view of the disposable diaper shown inFIG. 1 taken along section line 3--3 of FIG. 1;

FIGS. 4A-4D are simplified kinematic representations of the functioningof the elastic waist feature during use as the wearer (shown in thedrawings) moves from a standing position to a sitting position;

FIG. 5 is a fragmentary sectional view of an alternative disposablediaper embodiment of the present invention showing an alternativeconstruction of the elasticized waistband;

FIG. 5A is a fragmentary sectional view of a further alternativedisposable diaper embodiment of the present invention showing a furtheralternative construction of the elasticized waistband;

FIG. 6 is a fragmentary plan view of another alternative disposablediaper embodiment of the present invention showing an elastic waistfeature of an "expansive tummy panel" having differential extensibilityin the lateral direction and "windowed" elastic waist feature;

FIG. 7 is a fragmentary plan view of an alternative embodiment of theelastic waist feature shown in FIG. 6;

FIG. 8 is a simplified perspective view of an apparatus that employs avacuum web restraint system for mechanically stretching a portion of adiaper web using meshing corrugated rolls;

FIG. 8A is a simplified view taken along line 8A--8A in FIG. 8 showingthe manner in which idler rolls are used to cause the diaper web to wrapthe lowermost corrugated rolls;

FIG. 8B is a highly enlarged view taken at the inset 8B shown in FIG. 8,showing the degree of meshing of the corrugated rolls with one anotheras the "zero strain" stretch laminate portion of the diaper web passestherebetween;

FIG. 9 is a simplified perspective view showing an alternative webrestraint system of the present invention which may be used during theincremental stretching process disclosed herein;

FIG. 9A is a highly enlarged simplified cross-sectional view taken atinset 9A shown in FIG. 9 along a centerline connecting the uppermostcorrugated rolls and the lowermost corrugated rolls;

FIG. 10 is a simplified, fragmentary, enlarged plan view of thedisposable diaper of the present invention in the first waist regionshowing the location for taking test samples from the elastic waistfeature;

FIG. 11 is a perspective view of a test apparatus for measuring thebending flexure recovery force of the waistband flexural hinge zone ofthe elastic waist feature;

FIG. 12 is a representative graph of deflection force versus deflectiondistance of two cycles of the flexure bending test;

FIG. 13 is a perspective view of the test sample created according tothe test procedures for determining the edge compression stiffness of apanel zone of the elastic waist feature;

FIG. 14 is a simplified side view of the apparatus and test sample "setup" for determining the edge compression stiffness of a panel zone ofthe elastic waist feature; and

FIG. 15 is a representative graph of compression force versuscompression displacement of two cycles of the edge compression stiffnesstest.

DETAILED DESCRIPTION OF THE INVENTION

As used herein, the term "absorbent article" refers to devices whichabsorband contain body exudates, and, more specifically, refers todevices which are placed against or in proximity to the body of thewearer to absorb andcontain the various exudates discharged from thebody. The term "disposable" is used herein to describe absorbentarticles which are not intended to be laundered or otherwise restored orreused as an absorbent article (i.e., they are intended to be discardedafter a single use and, preferably, to be recycled, composted orotherwise disposed of in an environmentally compatible manner). A"unitary" absorbent article refers to absorbent articles which areformed of separate parts united together to form a coordinated entity sothat they do not require separate manipulative parts like a separateholder and liner. A preferred embodiment of an absorbent article of thepresent invention is the unitarydisposable absorbent article, diaper 20,shown in FIG. 1. As used herein, the term "diaper" refers to anabsorbent article generally worn by infantsand incontinent persons thatis worn about the lower torso of the wearer. It should be understood,however, that the present invention is also applicable to otherabsorbent articles such as incontinent briefs, incontinentundergarments, diaper holders and liners, feminine hygiene garments, andthe like.

FIG. 1 is a plan view of the diaper 20 of the present invention in itsflat-out, uncontracted state (i.e., with elastic induced contractionpulled out except in the side panels wherein the elastic is left in itsrelaxed condition) with portions of the structure being cut-away to moreclearly show the construction of the diaper 20 and with the portion ofthediaper 20 which faces away from the wearer, the outer surface 52,facing the viewer. As shown in FIG. 1, the diaper 20 comprises acontainment assembly 22 preferably comprising a liquid pervious topsheet24, a liquid impervious backsheet 26 joined with the topsheet 24, and anabsorbent core28 positioned between the topsheet 24 and the backsheet26; elasticized side panels 30; elasticized leg cuffs 32; an elasticwaist feature 34; anda closure system comprising a dual tensionfastening system generally multiply designated as 36. The dual tensionfastening system 36 preferablycomprises a primary fastening system 38and a waist closure system 40. The primary fastening system 38preferably comprises a pair of securement members 42 and a landingmember 44. The waist closure system 40 is shown in FIG. 1 to preferablycomprise a pair of first attachment components 46 and a secondattachment component 48. The diaper 20 also preferably comprises apositioning patch 50 located subjacent each first attachment component46.

The diaper 20 is shown in FIG. 1 to have an outer surface 52 (facing theviewer in FIG. 1), an inner surface 54 opposed to the outer surface 52,a first waist region 56, a second waist region 58 opposed to the firstwaistregion 56, and a periphery 60 which is defined by the outer edgesof the diaper 20 in which the longitudinal edges are designated 62 andthe end edges are designated 64. (While the skilled artisan willrecognize that a diaper is usually described in terms of having a pairof waist regions anda crotch region between the waist regions; in thisapplication, for simplicity of terminology, the diaper 20 is describedas having only waistregions, each of the waist regions including aportion of the diaper which would typically be designated as part of thecrotch region). The inner surface 54 of the diaper 20 comprises thatportion of the diaper 20 which is positioned adjacent to the wearer'sbody during use (i.e., the inner surface 54 generally is formed by atleast a portion of the topsheet 24 and other components joined to thetopsheet 24). The outer surface 52 comprises that portion of the diaper20 which is positioned away from the wearer's body i.e., the outersurface 52 generally is formed by at least aportion of the backsheet 26and other components joined to the backsheet 26). The first waist region56 and the second waist region 58 extend, respectively, from the endedges 64 of the periphery 60 to the lateral centerline 66 of the diaper20. The waist regions each comprise a central region 68 and a pair ofside panels which typically comprise the outer lateral portions of thewaist regions. The side panels positioned in the first waist region 56are designated 70 while the side panels in the second waist region 58are designated 72. (In the discussion that follows,unless otherwisenoted, the diaper 20 will comprise a pair of side panels in each waistregion. While it is not necessary that the pairs of side panels or eachside panel be identical, they are preferably mirror images one of theother). In a preferred embodiment of the present invention, thesidepanels 72 positioned in the second waist region 58 are elasticallyextensible in the lateral direction (i.e., elasticized side panels 30).(The lateral direction (x direction or width) is defined as thedirection parallel to the lateral centerline 66 of the diaper 20; thelongitudinal direction (y direction or length) being defined as thedirection parallel to the longitudinal centerline 67; and the axialdirection (Z direction orthickness) being defined as the directionextending through the thickness of the diaper 20.)

FIG. 1 shows a preferred embodiment of the diaper 20 in which thetopsheet 24 and the backsheet 26 have length and width dimensionsgenerally larger than those of the absorbent core 28. The topsheet 24and the backsheet 26 extend beyond the edges of the absorbent core 28 tothereby form the periphery 60 of the diaper 20. The periphery 60 definesthe outer perimeter or, in other words, the edges of the diaper 20. Theperiphery 60comprises the longitudinal edges 62 and the end edges 64.

FIG. 2 is a cross-sectional view of the diaper 20 taken along sectionline 2--2 of FIG. 1 in the first waist region 56. FIG. 2 shows theconstructionof the elasticized waistband 35 of the elastic waist feature34. The elasticized waistband 35 is shown in FIG. 2 in its contracted orrelaxed condition. The elasticized waistband 35 preferably comprises aportion of the topsheet 24, a portion of the backsheet 26 that haspreferably been mechanically stretched, and a bi-laminate materialcomprising an elastomeric member 76 positioned between the topsheet 24and the backsheet26 and a resilient member 77 positioned between thebacksheet 26 and the elastomeric member 76. The elasticized waistband 35is also provided with regions of securement 78 wherein the backsheet 26and the topsheet 24 are joined to the bi-laminate material of theelastomeric member 76 and the resilient member 77. Since the topsheet 24and the backsheet 26 are gathered when the bi-laminate material is inits relaxed condition, regions of differential securement are providedwhich form pleats 80.

FIG. 3 is a fragmentary cross-sectional view of the diaper 20 takenalong line 3--3 of FIG. 1 and depicts a preferred elastic waist featureconstruction in the first waist region 56. The absorbent core 28 isgenerally shown in FIG. 3 and shows the waist edge 83 of the absorbentcore 28. The topsheet 24 and the backsheet 26 encase the absorbent core28and extend longitudinally outwardly beyond the waist edge 83 of theabsorbent core 28 to form a waist flap 89 and the end edge 64. Theelasticwaist feature 34 extends longitudinally outwardly from the waistedge 83 ofthe absorbent core 28 in at least the central region 68 andforms at least a portion of the end edge 64. The elastic waist feature34 comprises an interconnecting panel zone 330, a first flexural hingezone 132 joining the interconnecting panel zone 130 with the containmentassembly 22 adjacent the waist edge 83 of the absorbent core 28, anelasticized waistband 35, and a second flexural hinge zone 134 joiningthe elasticizedwaistband 35 with the interconnecting panel zone 130. Asshown in FIG. 3, the elasticized waistband 35 comprises a shaping panelzone 136; a waistline panel zone 138; and a predisposed, resilient,waistband flexuralhinge zone 140 joining the shaping panel zone 336 andthe waistline panel zone 138. As shown in FIG. 3, the interconnectingpanel zone 130 comprisesa portion of the topsheet 24 and the backsheet26 while the elasticized waistband 35 comprises a portion of thetopsheet 24 and the backsheet 26 and the bi-laminate material of theelastomeric member 76 and the resilient member 77.

FIG. 2B is a simplified, fragmentary, enlarged plan view of thedisposable diaper 20 in the first waist region 56 showing generally thevarious zonesand elements of the elastic waist feature 34. The absorbentcore 28 Is generally shown and has the waist edge 83 and the side edges82. The panelzones of the elastic waist feature 34 are generallyrepresented by the shaded areas. The panel zones comprise theinterconnecting panel zone 130 and the elasticized waistband 35comprising the shaping panel zone 136 andthe waistline panel zone 138.The flexural hinge zones are generally depicted by lines even thoughthey may comprise regions or zones which have some significant width soas to exhibit bending/flexure deformation. The flexural hinge zonescomprise the first flexural hinge zone 132, the second flexural hingezone 134, and the waistband flexural hinge zone 140.The closure systemis shown as comprising a pair of first attachment components 46longitudinally aligned with the elasticized waistband 35 so as tomaintain/create lateral tension through the elasticized waistband 35.The first attachment component 46 preferably comprises a separate patchof material, preferably a hook fastening material, joined to thebacksheet 26.

The containment assembly 22 of the diaper 20 is shown in FIG. 1 ascomprising the main body (chassis) of the diaper 20. The containmentassembly 22 comprises at least an absorbent core 28 and preferably anouter covering layer comprising the topsheet 24 and the backsheet 26.Whenthe absorbent article comprises a separate holder and a liner, thecontainment assembly 22 generally comprises the holder and the liner(i.e., the containment assembly 22 comprises one or more layers ofmaterial to define the holder while the liner comprises an absorbentcomposite such as a topsheet, a backsheet, and an absorbent core.) Forunitary absorbent articles, the containment assembly 22 comprises themainstructure of the diaper with other features added to form thecomposite diaper structure. Thus, the containment assembly 22 for thediaper 20 generally comprises the topsheet 24, the backsheet 26, and theabsorbent core 28.

The absorbent core 28 may be any absorbent means which is generallycompressible, conformable, non-irritating to the wearer's skin, andcapable of absorbing and retaining liquids such as urine and othercertainbody exudates. As shown in FIG. 1, the absorbent core 28 has agarment surface 100, a body surface 101, side edges 82, and waist edges83.

The absorbent core 28 may be manufactured in a wide variety of sizes andshapes (e.g., rectangular, hourglass, "T"-shaped, asymmetric, etc.) andfrom a wide variety of liquid-absorbent materials commonly used indisposable diapers and other absorbent articles such as comminuted woodpulp which is generally referred to as airfelt. Examples of othersuitableabsorbent materials include creped cellulose wadding, meltblownpolymers including coform, cross-linked cellulosic fibers, tissueincluding tissue wraps and tissue laminates, absorbent foams, absorbentsponges, superabsorbent polymers, absorbent gelling materials, or anyequivalent material or combinations of materials. The configuration andconstruction of the absorbent core may also be varied (e.g., theabsorbent core may have varying caliper zones, a hydrophilic gradient, asuperabsorbent gradient, or lower average density and lower averagebasis weight acquisition zones; or may comprise one or more layers orstructures). The total absorbent capacity of the absorbent core 28should, however, be compatible with the design loading and the intendeduse of the diaper 20. Further, the size and absorbent capacity of theabsorbent core 28 may be varied to accommodate wearers ranging frominfants through adults.

A preferred embodiment of the diaper 20 has an asymmetric, modifiedT-shaped, absorbent core 28 having ears 102 in the first waist region 56but a generally rectangular shape in the second waist region 58. Thisconfiguration allows wider elasticized side panels 30 in the secondwaist region 58. An exemplary absorbent structure for use as theabsorbent core 28 of the present invention that has achieved wideacceptance and commercial success is described in U.S. Pat. No.4,610,678 entitled "High-Density Absorbent Structures" issued to Wetsmanand Goldman on Sep. 9, 3986. U.S. Pat. No. 4,673,402 entitled "AbsorbentArticles With Dual-Layered Cores" issued to Wetsman, Houghton, andGellert on Jun. 6, 1987; and U.S. Pat. No. 4,888,231 entitled "AbsorbentCore Having A Dusting Layer" issued to Angstadt on Dec. 9, 1989; alsodescribe absorbentstructures that are useful in the present invention.The absorbent core 28 is preferably the commercially successfulabsorbent member described in U.S. Pat. No. 4,834,735, entitled "HighDenstry Absorbent Members Having Lower Density and Lower Basis WeightAcquisition Zones", issued to Alemanyand Berg on May 30, 1989. Each ofthese references are incorporated herein by reference.

The backsheet 26 is positioned adjacent the garment surface 100 of theabsorbent core 28 and is preferably joined thereto by attachment means(not shown) such as those well known in the art. For example, thebacksheet 26 may be secured to the absorbent core 28 by a uniformcontinuous layer of adhesive, a patterned layer of adhesive, or an arrayof separate lines, spirals, or spots of adhesive. Adhesives which havebeen found to be satisfactory are manufactured by Century Adhesives,Inc. of Columbus, Ohio and marketed as Century 5227; and by H. B. FullerCompany of St. Paul, Minn. and marketed as HL-1258. The attachment meanswill preferably comprise an open pattern network of filaments ofadhesive as is disclosed in U.S. Pat. No. 4,573,986 entitled "DisposableWaste-Containment Garment", which issued to Minetola and Tucker on Mar.4,1986, and which is incorporated herein by reference. An exemplaryattachment means of an open pattern network of filaments comprisesseverallines of adhesive filaments swirled into a spiral pattern such asis illustrated by the apparatus and methods shown in U.S. Pat. No.3,911,173 issued to Sprague, Jr. on Oct. 7, 1975; U.S. Pat. No.4,785,996 issued to Ziecker, et al. on Nov. 22, 1978; and U.S. Pat. No.4,842,666 issued to Werenicz on Jun. 27, 1989. Each of these patents areincorporated herein by reference. Alternatively, the attachment meansmay comprise heat bonds,pressure bonds, ultrasonic bonds, dynamicmechanical bonds, or any other suitable attachment means or combinationsof these attachment means as areknown in the art.

The backsheet 26 is impervious to liquids (e.g., urine) and ispreferably manufactured from a thin plastic film, although otherflexible liquid impervious materials may also be used. As used herein,the term "flexible"refers to materials which are compliant and willreadily conform to the general shape and contours of the human body. Thebacksheet 26 prevents the exudates absorbed and contained in theabsorbent core 28 from wetting articles which contact the diaper 20 suchas bedsheets and undergarments. The backsheet 26 may thus comprise awoven or nonwoven material, polymericfilms such as thermoplastic filmsof polyethylene or polypropylene, or composite materials such as afilm-coated nonwoven material. Preferably, the backsheet is athermoplastic film having a thickness of from about 0.012 mm (0.5 mil)to about 0.051 mm (2.0 mils).

In a preferred embodiment of the present invention, at least a portionof the backsheet 26 is subjected to mechanical stretching in order toprovideboth a "zero strain" stretch laminate that forms the elasticizedside panels 30 and to prestrain the portion of the backsheet coincidingwith the elastic waist feature. Thus, the backsheet 26 is preferablyelongatable, most preferably drawable, but not necessarily elastomeric,sothat the backsheet 26 will, upon mechanical stretching, be at least toa degree permanently elongated such that it will not fully return to itsoriginal undistorted configuration. In preferred embodiments, thebacksheet can be subjected to mechanical stretching without unduerupturing or tearing. Thus, it is preferred that the backsheet 26 havean ultimate elongation to break of at least about 400% to about 700% inthe cross-machine direction as measured using a method consistent withASTH D-638. Thus, preferred polymeric films for use as the backsheetcontain a high content of linear low density polyethylene. Particularlypreferred materials for the backsheet include blends comprised of about45-90% linear low density polyethylene and about 10-55% polypropylene.Exemplary films for use as the backsheet of the present invention aremanufactured by Tredegar Industries, Inc. of Terre Haute, Ind. under thedesignation RR8220 blend for blown films and RR5475 blend for castfilms. The backsheet 26 is preferably embossed (typically, to a caliperof about 0.127 mm (5.5 mils)) and/or matte finished to provide a moreclothlike appearance. Further, the backsheet 26 may permit vapors toescape from theabsorbent core 28 (i.e., breathable) while stillpreventing exudates from passing through the backsheet 26.

The size of the backsheet 26 is dictated by the size of the absorbentcore 28 and the exact diaper design selected. In a preferred embodiment,the backsheet 26 has a modified hourglass shape extending beyond theabsorbentcore 28 a minimum distance of at least about 1.3 cm to about2.5 cm (about 0.5 to about 1.0 inch) around the entire diaper periphery60. Preferably, the backsheet 26 is much wider than the absorbent core28 in the second waist region 58 so that the side panels 72 in thesecond waist region 58 are generally wider in the lateral direction thanthe side panels 70 in the first waist region 56.

The topsheet 24 is positioned adjacent the body surface 101 of theabsorbent core 28 and is preferably joined thereto and to the backsheet26by attachment means (not shown) such as those well known in the art.Suitable attachment means are described with respect to joining thebacksheet 26 to the absorbent core 28. As used herein, the term "joined"encompasses configurations whereby an element is directly secured to theother element by affixing the element directly to the other element, andconfigurations whereby the element is indirectly secured to the otherelement by affixing the element to intermediate member(s) which in turnare affixed to the other element. In a preferred embodiment of thepresentinvention, the topsheet 24 and the backsheet 26 are joineddirectly to eachother in the diaper periphery 60 and are indirectlyjoined together by directly joining them to the absorbent core 28 by theattachment means (not shown).

The topsheet 24 is compliant, soft feeling, and non-irritating to thewearer's skin. Further, the topsheet 24 is liquid pervious permittingliquids (e.g., urine) to readily penetrate through its thickness. Asuitable topsheet may be manufactured from a wide range of materials,suchas porous foams; reticulated foams; apertured plastic films; orwoven or nonwoven webs of natural fibers (e.g., wood or cotton fibers),synthetic fibers (e.g., polyester or polypropylene fibers), or acombination of natural and synthetic fibers. Preferably, the topsheet 24is made of a hydrophobic material to isolate the wearer's skin fromliquids contained in the absorbent core 28.

In a preferred embodiment of the present invention, at least a portionof the topsheet 24 is subjected to mechanical stretching in order toprovide a "zero strain" stretch laminate that forms the elasticized sidepanels 30. Thus, the topsheet 24 is preferably elongatable, mostpreferably drawable, but not necessarily elastomeric, so that thetopsheet 24 will, upon mechanical stretching, be at least to a degreepermanently elongated such that it will not fully return to its originalconfiguration. In preferred embodiments, the topsheet 24 can besubjected to mechanical stretching without undue rupturing or tearing ofthe topsheet. Thus, it ispreferred that the topsheet 24 have a lowcross-machine direction (lateral direction) yield strength.

There are a number of manufacturing techniques which may be used tomanufacture the topsheet 24. For example, the topsheet 24 may be anonwoven web of fibers. When the topsheet comprises nonwoven web, theweb may be spunbonded, carded, wet-laid, meltblown, hydroentangled,combinations of the above, or the like. A preferred topsheet is cardedandthermally bonded by means well known to those skilled in the fabricsart. Apreferred topsheet comprises staple length polypropylene fibershaving a denlet of about 2.2. As used herein, the term "staple lengthfibers" refers to those fibers having a length of at least about 15.9 mm(0.625 inches). Preferably, the topsheet has a basis weight from about18 to about 25 grams per square meter. A suitable topsheet manufacturedby Veratec, Inc., a Division of International Paper Company, of Walpole,Mass. under the designation P-8.

The diaper 20 preferably further comprises elasticized leg cuffs 32 forproviding improved containment of liquids and other body exudates. Eachelasticized leg cuff 32 may comprise several different embodiments forreducing the leakage of body exudates the leg regions. (The leg cuff canbe and is sometimes also referred to as leg bands, side flaps, barriercuffs, or elastic cuffs. ) U.S. Pat. No. 3,860,003 entitled"Contractable Side Portions For a Disposable Diaper" issued to Buell onJan. 14, 1975, describes a disposable diaper which provides acontractible leg opening having a side flap and one or more elasticmembers to provide an elasticized leg cuff (gasketing cuff). U.S. Pat.No. 4,909,803 entitled "Disposable Absorbent Article Having ElasticizedFlaps" issued to Aziz andBlaney on Mar. 20, 1990, describes a disposablediaper having "stand-up" elasticized flaps (barrier cuffs) to improvethe containment of the leg regions. U.S. Pat. No. 4,695,278 entitled"Absorbent Article Having Dual Cuffs" issued to Lawson on Sep. 22, 1981,describes a disposable diaper having dual cuffs Including a gasketingcuff and a barrier cuff. U.S. Pat.No. 4,704,115 entitled "DisposableWaist Containment Garment" issued to Buell on Nov. 3, 1987, discloses adisposable diaper or incontinent garment having side-edge-leakage-guardgutters configured to contain free liquids within the garment. Each ofthese patents are incorporated herein by reference. While eachelasticized leg cuff 32 may be configured so as to be similar to any ofthe leg bands, side flaps, barrier cuffs, or elastic cuffs describedabove, it is preferred that each elasticized leg cuff 32 comprise atleast an inner barrier cuff 84 comprising a barrier flap 85 and aspacing elastic member 86 such as described in the above-referenced U.S.Pat. No. 4,909,803. In a preferred embodiment, the elasticized leg cuff32 additionally comprises an elastic gasketing cuff 104 with one or moreelastic strands 105, positioned outboard of the barrier cuff 84 such asdescribed in the above-referenced U.S. Pat. No. 4,695,278.

The diaper 20 further comprises an elastic waist feature 34 thatprovides improved fit and containment. The elastic waist feature 34 atleast extends longitudinally outwardly from at least one of the waistedges 83 of the absorbent core 28 in at least the central region 68 andgenerally forms at least a portion of the end edge 64 of the diaper 20.Thus, the elastic waist feature 34 comprises that portion of the diaperat least extending from the waist edge 83 of the absorbent core 28 tothe end edge 64 of the diaper 20 and is intended to be placed adjacentthe wearer's waist. Disposable diapers are generally constructed so asto have two elastic waist features, one positioned in the first waistregion and one positioned in the second waist region. While a disposablediaper of the present invention can be constructed with a single elasticwaist feature encircling the wearer, the discussion regarding theelastic waist feature will focus on diapers having a pair of elasticwaist features, at least one, and preferably both, being constructedaccording to the present invention. Further, while the elastic waistfeature or any of its constituent elements can comprise a separateelement affixed to the containment assembly 22 of the diaper 20, theelastic waist feature 34 will be described with respect to a preferredembodiment in which the elastic waist feature 34 is constructed as anextension of other elements of the diaper such as the backsheet 26 orthe topsheet 24, preferably boththe backsheet 26 and the topsheet 24.

While the elastic waist feature 34 need only comprise an elasticizedwaistband and a flexural hinge zone joining the elasticized waistbandwiththe containment assembly; as shown in FIG. 3, the elastic waistfeature 34,preferably comprises several additional zones. In particular,the elastic waist feature 34, comprises an interconnecting panel zone130, a first flexural hinge zone joining the interconnecting panel zone130 with the containment assembly 22 adjacent the waist edge 83 of theabsorbent core 28, an elasticized waistband 35, and a second flexuralhinge zone 134 joining the elasticized waistband 35 with theinterconnecting panel zone 130. The interconnecting panel zone 130preferably provides a flexible link between the elasticized waistband 35and the containment assembly 22.The elasticized waistband 35 provides amember that maintains a defined area coverage, contacts the wearer'swaist, and is elastically extensible in at least the lateral directionso as to dynamically fit against the waist of the wearer and todynamically conform to the waist of the wearer so as to provide improvedfit. As shown in FIG. 3, the elasticized waistband 35 comprises ashaping panel zone 136; a waistline panel zone 138; and a predisposed,resilient, waistband flexural hinge zone 140 joining the shaping panelzone 136 and the waistline panel zone 138. As used herein, the term"zone" is used to denote an area or element of the elastic waist feature34. While a zone of the elastic waist feature 34 maybe a distinct areaor element; typically, a zone of the elastic waist feature will overlapsomewhat with an adjacent zone(s). (For illustration purposes, the zonesare delineated with brackets in FIG. 3.)

The interconnecting panel zone 130 provides a link between theelasticized waistband 35 and the containment assembly 22 to allowrotations and translations of the elasticized waistband 35 so that theelasticized waistband may move in functional contacting position andconform with the waist of the wearer. The interconnecting panel zone 130is preferably flexible so that the interconnecting panel zone is free todeform randomlythroughout its length and width so as to allow theelasticized waistband 35to maintain contact with the waist of the wearerand to allow the absorbentcore 28 to position itself during wear. Whilethe interconnecting panel zone 330 may have a significant edgecompression stiffness; in a preferredembodiment, the interconnectingpanel zone is flexible such that the edge compression stiffness of theInterconnecting panel zone is preferably substantially less than theedge compression stiffness of both the shapingpanel zone 136 and thewaistline panel zone 138. It is preferred that the interconnecting panelzone 130 have an edge compression stiffness less than about 50grams_(f), more preferably less than about 25 grams_(f).Typically, theedge compression stiffness of the interconnecting panel zone(comprisinga portion of the topsheet 24 and a portion of the backsheet 26 joinedtogether) is less than about 10 grams_(f). Further, while theincterconnecting panel zone 130 may be elastically extensible in thelongitudinal direction, the lateral direction, or in any otherdirection, the interconnecting panel zone is preferably longitudinallynonextensible to provide a fixed dimension length between theelasticized waistband 35 and the containment assembly 22. The length ofthe interconnecting panel zone 130 is preferably at least about 4.75 mm(about 3/16 inch), more preferably between about 6.25 mm (about 1/4inch) and about 12.5 mm (about 1/2 inch) for medium-sized diapers.

The interconnecting panel zone 130 may be constructed from a separatematerial flexurally joined to the containment assembly 22 and/or theelasticized waistband 35, or as an extension of other elements of thediaper 20. In a preferred embodiment as shown in FIG. 3, theInterconnecting panel zone 130 comprises a portion of both the topsheet24and the backsheet 26 extending beyond the waist edge 83 of theabsorbent core 28. The backsheet 26 and the topsheet 24 are preferablyjoined to each other (joined together) by an attachment means (notshown) in the interconnecting panel zone 130 so that they perform as aunit rather than independently of each other. The attachment means forsecuring the topsheet 24 and the backsheet 26 to each other preferablycomprises an open pattern network of adhesive deposited in a spiral orlooping pattern,although other attachment means as describedhereinbefore may also be used.

The interconnecting panel zone 130 is flexurally joined with thecontainment assembly 22 and the shaping panel zone 136 by flexural hingezones (first flexural hinge zone 132 and second flexural hinge zone 134,respectively) so that the elasticized waistband 35 may translate and/orrotate in the axial direction (Z-direction). As used herein, the term"flexurally joined" means a joint between panel zones or a panel zoneand the containment assembly adapted to allow relative flexural bendingbetween the panel zones. (As discussed hereinafter, this flexuralbending is not necessarily such that the panel zones will return totheir previousconfiguration when the forces causing the flexural bendingare removed (i.e., they are not necessarily resilient).

A flexural hinge zone can be constructed in various ways. The flexuralhinge zone may comprise a zone of structural discontinuity between panelzones. The cross-sectional configuration of the panel zones may bevaried to allow flexural bending between the panel zones. For example,the materials making up the panel zones can be scored, compressed,embossed, creased, folded, bonded, reduced, cut, notched, slit, oreliminated to form an axis or axes of flexural bending. Typically, thesemethods will concentrate stresses/tensions to a particular line or axesthrough which flexural bending can occur. A line of reduced extension ora line of restraint may also be formed between zones to form a hingezone. As an alternative, the flexural hinge zone may comprise a zone ofmaterial discontinuity between the panel zones. For example, thematerials making up the panel zones may have a relative differentmodulus of bending or elasticity to provide an area or zone of differentflexural resistance (differential bending stiffness between the zones)which allows flexural bending between the panel zones.

As shown in FIG. 3, the second flexural hinge zone 134 joining theelasticized waistband 35 (shaping panel zone 136) with theinterconnectingpanel zone 130 is formed at the zone where there is astructural discontinuity due to the elimination of the elastomericmember 76 and the resilient member 77 from the interconnecting panelzone 130. Thus, the second flexural hinge zone 134 is created adjacentthe bottom edge of the elastomeric member 76 and the resilient member77. The first flexural hinge zone 132 joining the interconnecting panelzone 330 with the containment assembly 22 is formed at the zone wherethere is a structural discontinuity due to the absence of the absorbentcore 28 from the interconnecting panel zone 130.

The elasticized waistband 35 is that portion or zone of the diaper 20whichis intended to elastically expand and contract and to dynamicallyfit the wearer's waist. While the elasticized waistband 35 can comprisea separateelement flexurally joined with the interconnecting panel zone130, the elasticized waistband 35 is preferably formed as an extensionof the topsheet 24 or the backsheet 26, and, most preferably, thetopsheet 24 andthe backsheet 26. The elasticized waistband 35 ispreferably that portion of the elastic waist feature 34 extending fromthe second flexural hinge zone 134 to, preferably but not necessarily,the end edge 64 of the diaper20. In a preferred embodiment shown tn FIG.3, the elasticized waistband 35comprises a shaping panel zone 136; awaistline panel zone 138; and a predisposed, resilient, waistbandflexural hinge zone 140 joining the shaping panel zone 136 and thewaistline panel zone 138.

The shaping panel zone 136 is the portion of the elasticized waistband35 that is positioned between the waistband flexural hinge zone 140 andthe second flexural hinge zone 134. The shaping panel zone 136 thus willtypically define the "lower segment" of the elasticized waistband 35.The shaping panel zone 136 is elastically extensible in at least thelateral direction to allow dynamic expansion and contraction of theelasticized waistband during use. The shaping panel zone 136, as laterdiscussed, alsopreferably has a relatively significant edge compressionstiffness so that the shaping panel zone 136 will not rope, deform, orcompact in use and sothat the shaping panel zone 136 will maintain itsshape to resist compression and buckling of the elasticized waistbandduring use.

The waistline panel zone 138 is the portion of the elasticized waistband35that is positioned toward the end edge of the diaper from thewaistband flexural hinge zone 140. The waistline panel zone 138 thuswill generally define the "upper segment" of the elasticized waistband35. The waistline panel zone 138 will preferably form at least a portionof the end edge of the diaper 20. The waistline panel zone 138 isdesigned to snugly fit against the waist of the wearer and todynamically move, expand, and contract with the waist of the wearer. Thewaistline panel zone 138 is elastically extensible in at least thelateral direction.

The edge compression stiffness of the shaping panel zone 136 and thewaistline panel zone 138 determines the resistance generally of theelasticized waistband 35 to compression deformation and bending in eachzone. In a preferred embodiment of the present invention, the shapingpanel zone 136 has a substantial, predetermined, edge compressionstiffness to allow the shaping panel zone to resist compression andbending forces applied to it and to maintain the shape of theelasticized waistband when applied to the wearer. Also, the shapingpanel zone 136 preferably has an edge compression stiffness greater thanor equal to the edge compression stiffness of the waistline panel zone138. In a preferredembodiment of the present invention, since theshaping panel zone 136 and the waistline panel zone 138 are constructedof the same materials, the edge compression stiffness of the shapingpanel zone 136 is about equal tothe edge compression stiffness of thewaistline panel zone 138. It has beenfound that the shaping panel zone136 preferably has an edge compression stiffness greater than about 100grams_(f), more preferably greater thanabout 115 grams_(f), mostpreferably greater than about 130 grams_(f). Typically, in preferredembodiments of the present invention, the edge compression stiffness ofthe shaping panel zone 136 is between about 130 and about 170 grams_(f).The edge compression stiffness of a panel zone of the electric waistfeature 34, can be determined using the method as hereinafter described.

The waistline panel zone 138 is resiliently/flexurally joined with theshaping panel zone 136 by the waistband flexural hinge zone 140, As usedherein, the term "resiliently/flexurally joined" means a joint betweenpanel zones or a panel zone and the containment assembly adapted toallow relative flexural bending between the panel zones when forces areapplied that provides m restoring force/moment to resiliently return thepanel zones to essentially their preceding configuration when the forcesare removed. This restoring force/moment is important in the functioningof the elasticized waistband 35 so that the shaping panel zone 136 andthe waistline panel zone 138 will assume their preceding in-use(pretensioned)configuration so that the elasticized waistbanddynamically follows the waist of the wearer with little slippingrelative to the wearer during theentire time of wearing, and does notallow the elasticized waistband to disfunctionally crumple or foldoverin a manner that alters its intended functionality during use.

The waistband flexural hinge zone 140 is resilient to allow flexuralbending between the shaping panel zone 136 and the waistline panel zone138 when forces generated by the waist of the wearer during use areapplied and to return the shaping panel zone 136 and the waistline panelzone 138 to essentially their preceding in-use (pretensioned)configuration when these forces are removed by providing a restoringforce/moment. In a preferred embodiment shown in FIGS. 1-3, thewaistband flexural hinge zone 140 is constructed to be resilient byproviding a resilient member 77 in the elasticized waistband 35. It hasbeen found that in order to provide the necessary resiliency for thewaistband flexural hinge zone and to overcome the normal forcesencountered during wear of the diaper so as to reduce rollover orroll-in, the waistband flexural hinge zone 140 should have a bendingflexure restoring force greater than about 20 grams_(f), more preferablygreater than about 25 grams_(f), and most preferably greater than about30 grams_(f). In preferred embodiments of the present invention, thewaistband flexural hinge zone will have a bending flexure restoringforce between about 30 grams_(f) and about 50 grams_(f). A method formeasuring the bending flexure restoring force of a flexural hinge zone,particularly the waistband flexural hinge zone, is hereinafterdescribed. The waistband flexural hinge zone 140 is also "predisposed"so that the waistline panel zone 138 and the shaping panel zone 136 willflexurally bend at a defined zone or axes in the elasticized waistband35 for each given application offorce to the elasticized waistband 35.This predisposition of the waistbandflexural hinge zone 140 also allowsthe elasticized waistband to flexurallydeflect and follow the waist ofthe wearer without creasing or destroying the flexural rigidity of thematerials making up the elasticized waistband. Thus, a "predisposed"waistband flexural hinge zone will reducethe tendency for theelasticized waistband to bend or fold at random zones or axes duringuse. The "predisposed" waistband flexural hinge zone is defined by themanufacturer of the diaper to ensure flexural bending deflection at thedefined hinge zone. The formation of the waistband flexural hinge zone140 itself typically predisposes the axes or zone of flexural bendingwithin the elasticized waistband 35. As previously discussed, a flexuralhinge zone may comprise a zone of structural discontinuity or a zone ofmaterial discontinuity. These zones of discontinuity will define theaxis of flexural bending. As an example, thewaistband flexural hingezone 140 may comprise an axes or line created by embossing, creasing, orfolding the elasticized waistband along a defined line. For instance theelasticized waistband could be prefolded by the manufacturer inside ofthe packaging for the article to preshape or preform a waistbandflexural hinge zone in the elasticized waistband. A line of reducedextension (or the reverse of a line being extensible and the surroundingareas being nonextensible) may be provided to form the waistbandflexural hinge zone by providing spaced apart bands or lines of glue,thread, or other materials that provide a structural discontinuitybetween them in order to predispose the waistband flexural hinge zone. Achange in the lamination or bonding pattern or technique may also formthewaistband flexural hinge zone. Any of the other ways of creating aflexuralhinge zone previously discussed herein may also be used to formthe waistband flexural hinge zone.

In a preferred embodiment as shown in FIGS. 1 and 2B, the waistbandflexural hinge zone 140 is formed by a structural discontinuity betweenthe shaping panel zone 136 and the waistline panel zone 138. As shown inFIG. 2B, the materials forming the elasticized waistband 35 are securedtoeach other at transverse regions of securement 78 preferablycomprising a pattern of discrete, spaced, securement zones 79, mostpreferably the securement zones comprising dynamic mechanical bonds. Dueto the combined effect of the bonding pattern and the formation ofpleats in the waistband, the elasticized waistband 35 will tend to morereadily flexurally bend along the region in the pattern where there arefewer bonds. Thus, the pattern for the dynamic mechanical bonds, asshown in FIG. 2B, is designed as longitudinally staggered butoverlapping rows suchthat a lateral line moved longitudinally along theelasticized waistband will encounter the bonds except at the desiredlocation of the waistband flexural hinge zone. Thus, the waistbandflexural hinge zone 140 preferably comprises (is formed by) adiscontinuity in the pattern of the spacing of the securement zones 79.

The elasticized waistband 35 may be constructed in a number of differentconfigurations Including those described herein with regard to formingan elasticized side panel. In a preferred embodiment as shown in FIG. 2,the elasticized waistband 35 preferably is constructed from fourmaterials laminated together. The elasticized waistband 35 preferablycomprises a portion of the topsheet 24; a portion of the backsheet 26,this portion ofthe backsheet being preferably "mechanically prestrained"an elastomeric member 76; and a resilient member 77. The elastomericmember 76 and the resilient member 77 are preferably joined together,preferably by dynamic mechanical bonds, to form an elastic laminateprior to being combined withthe topsheet 24 and the backsheet 26. Thisbi-laminate is preferably positioned between the topsheet 24 and thebacksheet 26 with the resilientmember 77 disposed toward the backsheet26 and the elastomeric member 76 disposed toward the topsheet 24. Thus,the elastomeric member 76 is preferably positioned between the topsheet24 and the prestrained backsheet 26 with the resilient member 77preferably being positioned between the prestrained backsheet 26 and theelastomeric member 76.

The elastomeric member 76 is operatively associated with the elasticizedwaistband 35, preferably between the topsheet 24 and the backsheet 26,so that the elastomeric member 76 allows the elasticized waistband 35 tobe elastically extensible in the lateral direction (i.e., laterallyelastically extensible), and so that it can contractively return to itssubstantially unrestrained configuration. The elastomeric member 76 canbeoperatively associated in the elasticized waistband 35 in a number ofdifferent ways. As an example, the elastomeric member may be operativelyassociated in an elastically contractible condition so that theelastomeric member gathers or contracts the elasticized waistband. (Amoredetailed description of the manner in which elastomeric materialsmay be secured in an absorbent article in an elastically contractiblecondition can be found in U.S. Pat. No. 3,860,003 issued to Buell onJan. 14, 1975, and in U.S. Pat. No. 4,081,301 issued to Buell on Mar.28, 1978; both patents being incorporated herein by reference.) Forexample, the elastomeric members 76 can be contractibly affixed in theelasticized waistband 35 by laterally extending the elastomeric member76, affixing the elastomeric member 76 to either or both the topsheet 24and the backsheet 26, and allowing the elastomeric member 76 to assumeits relaxedor contracted orientation.

Alternatively, the elastomeric member 76 can be operatively associatedin the elasticized waistband 35 by securing the elastomeric member 76 tothe topsheet 24, the backsheet 26, or both while the elastomeric member76 is in a substantially untensioned condition, at least a portion ofthe laminate containing the elastomeric member 76 then being subjectedto mechanical stretching sufficient to permanently elongate the topsheet24 and the backsheet 26 components of the laminate, and then thecomposite orelastomeric laminate is returned to its substantiallyuntensioned condition. The elasticized waistband 35 is thus formed intoa "zero strain" stretch laminate. (As discussed hereinafter, theelastomeric laminate may alternatively be operatively associated in atensioned condition and subjected to mechanical stretching to form amechanically stretched, pretensioned, stretch laminate.)

In an especially preferred embodiment as shown in FIG. 2, theelastomeric member 76 can be operatively associated in an uncontractedstate and then treated to contract. In this embodiment, the elastomericmember 76 can be formed from materials which contract unidirectionallyand become elastic following specific treatment such as heating.Examples of such materials are disclosed in U.S. Pat. No. 3,819,401issued to Massengale, et al. on Jun. 25, 1974 and in U.S. Pat. No.3,912,565 issued to Koch, et al. on Oct. 14, 1975. A more detaileddescription of a manner for using a heat-shrinkable elastomeric memberis described in U.S. Pat. No. 4,515,595issued to Kievit and Osterhage onMay 7, 1985; this patent being incorporated herein by reference.Typically, the topsheet 24, the backsheet 26, the elastomeric member 76,and any other components are secured together while in an uncontractedcondition. The laminate is then heated (as with heated air) and theelastomeric member 76 is allowed to return to its relaxed or contractedorientation.

The elastomeric members useful in the present invention may take on anumber of different sizes, shapes, configurations, and materials. Forexample, the elasticized waistband may be formed from one or a pluralityof elastomeric members operatively associated between the topsheet andthebacksheet; the elastomeric member may have varying widths andlengths; or the elastomeric member may comprise relatively narrowstrands of elastomeric material or a larger area patch of elastomericmaterial. One elastomeric material which has been found to be suitablefor use as the elastomeric member is an elastomeric foam such as thepolyurethane foam such as is available from Bridgestone of Yokahama,Japan and designated Bridgestone SG Polyurethane Foam. Other suitableelastomeric materials foruse as the elastomeric member include "live"synthetic or natural rubber, elastomeric films (includingheat-shrinkable elastomeric films), formed elastomeric scrim, or thelike. In an especially preferred embodiment as is shown in FIG. 2, theelastomeric member 76 comprises a heat-shrinkable elastomeric film suchas marketed by Exxon Chemical Company of Florham Park, N.J.

The resilient member 77 is a layer or layers that provides enhancedshape recovery and bending stiffness to the elasticized waistband 35.The resilient member 77 provides compression/buckling resistance in thelongitudinal direction (machine direction) so that the waistbandflexural hinge zone 140 will be resilient so as to provide a restoringforce/moment. The resilient member 77 also has a relatively high caliperto provide a Z-direction bulk so as to somewhat fill the pleats 80 orrugosities of the elasticized waistband 35 so as to optimize itsresiliency. The resilient member 77 is also preferably hydrophobic toprevent wicking of liquids out of the elasticized waistband 35. In anespecially preferred embodiment, the resilient member 77 comprises anonwoven material in which the fibers are oriented in the machinedirection (longitudinal direction of the diaper) to reduce cross machinedirection (lateral) gather resistance so that the heat shrinkableelastomeric member can readily contract and to enhance the compressionresistance about a defined axes of bending, the waistband flexural hingezone 140.

While the resilient member 77 is preferably positioned between theelastomeric member 76 and the backsheet 26 as shown in FIG. 3, theresilient member 77 may alternatively be positioned between the topsheet24 and the el astomeric member 76, on the outside of the backsheet 26,on the outside of the topsheet 24, or in a number of otherconfigurations. The resilient member 77 is preferably positioned betweenthe backsheet 26 and the elastomeric member 76 to provide greatercompression/buckling resistance on the backsheet side of the elasticizedwaistband 35 since it will fill the rugosities or pleats 80 in thelongitudinal axis between thebond sites, for providing bendingresistance about the lateral axis of the elasticized waistband, and tooptimize and reduce wicking in the laminate material forming theelasticized waistband.

The resilient member 77 may take on a number of different sizes, shapes,configurations, and materials. For example, the resilient member may beformed from one or a plurality of resilient members; the resilientmember may have varying widths, lengths, thickness, and shapes. Theresilient member 77 preferably comprises a separate piece of materialpositioned in the elasticized waistband. Alternatively, the resilientmember may comprise a portion of any or all of the materials making upthe elasticized waistband 35, including the elastomeric member 76, thetopsheet 24, or the backsheet 26. In a particular alternativeembodiment, the resilient member 77 comprises the same piece as theelastomertc member76, the elastomertc member 76 comprising a relativelythick elastomertc foam.

Suitable materials for use as the resilient member 77 of the elasticizedwaistband 35 of the present invention include woven webs; nonwoven webs;foams; laminate materials including film laminates of nonwoven laminatesof two or more nonwoven layers; scrims; corrugated materials thatprovide stiffness in at least one direction; and any combination of theabove materials or other materials as are known in the art.

Particularly preferred materials for the resilient member 77 comprisenonwoven webs that are hydrophobic and that have a drapability (asmeasured using ASTN B1388-64) of at least about 4 cm in the crossmachine direction and at least about 12 cm in the machine direction. Anexemplary material comprises a hydrophobic, nonwoven carded web having abasis weight in the range of from about 20-45 grams per square yard. Thefibers are oriented in the machine direction to provide enhancedbuckling/compression resistance in this direction. The nonwoven web iscomprised of 3 denier bicomponent fibers of polyester core material andcopolyolefin sheathing material, such fibers being available from Hoechtas CELBOND stable fibers; or of a polypropylene core material andpolyethylene sheathing material, such fibers being available fromDanaklonor Hercules. After carding the nonwoven web to orient the fibersin the machine direction, the nonwoven web is put through an air-thrubonding process to provide bulk (loft or thickness) to the resilientmember to enhance its resiliency. (Examples of high loft nonwoven websof bicomponent thermoplastic resin fibers that are air-thru bonded aredisclosed in U.S. Pat. No. 4,883,707 issued to Newkirk on Nov. 28, 1989,and incorporated herein by reference.) Exemplary air-thru bondednonwoven carded webs of bicomponent thermoplastic fibers are availablefrom Fiberweb North America of Greenville, N.C. Carolina or from VeratecCorporation of Walpole, Mass.

In a preferred embodiment of the present invention as shown in FIG. 2A,theportion of the backsheet 26 forming the elasticized waistband 35 hasbeen "prestrained" or "mechanically prestrained" (i.e., subjected tosome degree of localized pattern mechanical stretching to permanentlyelongate those portions of the backsheet forming the elasticizedwaistband 35). A prestrained backsheet improves not only the extensionof the elastomeric member 76 but also the heat-shrink contraction of thepreferred elastomertc members 76. In a preferred embodiment as shown inFIG. 2A, theprestrained backsheet assumes a pattern of ribs 142(strained portions) andunstrained gaps 144 between each rib 142 andbetween each row of ribs. Thispattern is determined by the method andapparatus used to prestrain the backsheet. In this preferred embodiment,the ribs are 0.25 inch (about 6 mm) long, 0.030 inch (about 0.75 mm)wide, have a depth of 0.125 inch (about 3 mm), with a spacing betweeneach rib (gap) of 0.100 inch (about 2.5 mm). The area of the backsheetthat is prestrained preferably about 5.5 inches (about 140 mm) wide byabout 1 inch (about 25 mm) in length.

The backsheet 26 of the present invention can be prestrained bydirecting the backsheet through an incremental mechanical stretchingsystem similar to the operation described herein with respect to theformation of the "zero strain" stretch laminate elasticized side panels30, prior to combining the backsheet into the finished diaper product.The corrugated or grooved segments contained on the rolls areinterrupted to bring about the pattern of ribs in the machine directionand the cross-machine direction. The registration of the web of thebacksheet is such that the portion of the backsheet to be prestrainedsubstantially coincides with the corrugated or grooved segmentscontained on the uppermost corrugated rolls as the backsheet passesbetween the segments of the uppermost corrugated rolls and thecorrugated or grooved lowermost corrugated rolls.The backsheet canalternatively be prestrained by using deep embossing techniques as areknown in the art.

In a preferred method for making the diapers of the present invention,after the backsheet web has been prestrained, and after the backsheetweb has been removed from the corrugated combining rolls, a continuousspray glue is applied to the backsheet web. The elastic laminatecomprising the resilient member and the heat-shrinkable elastomericmember is dynamicallymechanically bonded with the topsheet. Theresulting topsheet/elastomeric member/resilient member laminate is thenapplied to the prestrained backsheet web of the diaper and dynamicallymechanically bonded together to form the elasticized waistband 35. Thisdiaper web is then passed to a heat shrink apparatus to contract theheat shrinkable elastomeric member.

The elasticized waistband 35 further comprises transverse regions ofsecurement 78 shown in a generalized representation in FIG. 1 and inFIG. 2. A more detailed description of the transverse regions ofsecurement andalternative configurations for them are found in U.S. Pat.No. 4,515,595 issued to Kievit and Osterhage on May 7, 1985, and whichpatent is incorporated herein by reference. The transverse regions ofsecurement 78 extend essentially across the full width of theelasticized waistband 35, particularly the elastomeric member 76. Theterm "essentially across" is used in this context to indicate that thetransverse regions of securementneed not extend absolutely across theentire width of the elastomeric member 76 so long as they extendsufficiently far across the width to provide the function discussedhereinafter. As illustrated, the transverseregions of securement 78 areshown to be disposed at essentially a right angle to the lateralcenterline 66 and to the lateral extent of the elasticized waistband 35.This is the preferred orientation. One can, however, depart from truetransversity without departing from the scope and spirit of theinvention.

In FIGS. 1 and 2B, the transverse regions of securement 78 are shown asdiscrete, spaced, securement zones 79 effectively attaching the webs ofmaterial forming the elasticized waistband 35 (the topsheet 24, thebacksheet 26, the resilient member 77, and the elastomertc member 76 ina preferred embodiment) together. While the shape of the discretesecurementzones may vary, the discrete securement zones 79 arepreferably circular, elliptical, oval, rectangular, or square shaped.The discrete securement zones 79 are preferably regularly spaced in apattern (as shown in Fibre 2B) (except where the waistband flexuralhinge zone 140 is formed), although they can be nonuniformly spaced. Theprecise means for providing the securement zones 79 can be readilyselected by those skilled in the art. Examples of such attachment meansinclude adhesive attachment, heat sealing, solvent sealing, autogeneousbonding, dynamic mechanical bonding,ultrasonic welding, and the like.Preferably, the transverse regions of securement 78 comprise oval(rounded rectangular) shaped discrete securement zones 79, preferablydynamic mechanical bonds, such as described in U.S. Pat. No. 4,919,738entitled "Dynamic Mechanical Bonding Method And Apparatus" which issuedto Ball, Goulait & Zorb on Apr. 24, 1990, and which patent isincorporated herein by reference, disposed in rows and columns with onecolumn missing or irregularly spaced to form thewaistband flexural hingezone 140. The securement zones 79 are preferably from about 2.0 mm(about 0.078 in) by about 1.3 mm (about 0.52 in) and are preferablyspaced from about 7.0 mm (0.275 in) to about 8.9 mm (0.375 in) fromcenter to center in the transverse direction and from about 1.9 mm(0.375 in) to about 3.8 mm (0.15 in) from center to center in thelongitudinal direction. (One row of bond sites are eliminated in eachcolumn such that there is a longitudinal gap of about 1.0 mm (about0.040 in) to about 3.8 mm(0.150 in) from center to center to form thewaistband flexural hinge zone 140.) In the most preferred embodiment,the securementzones 79 are spaced about 8.3 mm (0.325 in) from center tocenter in the transverse direction and about 2.8 mm (0.112 in) fromcenter to center in the longitudinal direction with an offset gapspacing of about 0.11 mm (0.028 in) from center to center betweenadjacent rows in the longitudinaldirection.

As illustrated in FIG. 2, the discrete securement zones 79 on eitherside of the elastomeric member 76 are in register (i.e., they arecoextensive).This is a preferred orientation, but the discretesecurement zones 79 of the topsheet 24 to the elastic laminate materialcan be offset from the adjacent discrete securement zones 79 of thebacksheet 26 to the elastic laminate material.

In an alternative embodiment, the elasticized waistband in the secondwaistregion 58 (or the first waist region 56 if elasticized side panelsare disposed therein) and the elasticized side panels 30 can be formedby securing a single piece of elastomeric material to the diaper 20 inboth the side panels 72 and the central region 68 of the second waistregion 58. Thus, the elasticized waistband 35 and the elasticized sidepanels 30 can be formed from the same piece of material to form aunitary structure.An example of such an elasticized waistband/side panelconfiguration is disclosed in the hereinbefore referenced U.S. Pat. No.4,887,067 issued toWood, et al. on Aug. 15, 1989, and which patent isincorporated herein by reference.

In a further alternative embodiment of the present invention, theelasticized waistband 35 may have differential extensibility along thelongitudinal axis when stretched in the lateral direction. Thedifferential extensibility of the elasticized waistband 35 allowsportionsto laterally expand to a greater degree than other portionsalong the longitudinal axis. This differential extensibility of theelasticized waistband provides an abdominally compliant elasticizedwaistband, "expansive tummy panel", that allows the elasticizedwaistband to differentially shape, expand and move with the stomach ofthe wearer as the wearer moves, sits, and stands. Differentialextensibility along the longitudinal axis when stretched in the lateraldirection of the elasticized waistband can be achieved in a number ofways such as is discussed with respect to the elasticized side panels30. As shown in FIG.6, a preferred differential extensibilityelasticized waistband has a pentagonal shape.

The diaper 20 is also preferably provided with a closure system(tensioningmeans) for dynamically creating/maintaining lateral tensionthrough the elasticized waistband 35. The lateral tension dynamicallycreated and maintained by the closure system "activates" the stretch ofthe elasticized waistband 35 thereby allowing it to more dynamicallyexpand and contract with the motions of the wearer. Gapping of theelasticized waistband is also reduced by the activated stretch since itis held in tension to snugly fit against the wearer's waist both whenthe diaper is initially fitted to the wearer and during use. Further,rollover of the elasticized waistband is reduced by the tensioncreated/maintained by the closure system. Thus, the closure systemimproves the fit and containment characteristics of the diaper.

While the closure system may take on a number of configurations such asadhesive tape tabs, mechanical closure tape tabs, fixed positionfasteners, or any other means for tensioning the elasticized waistbandas are known in the art; as shown in FIG. 1, the closure systempreferably comprises a waist closure system 40 comprising at least one,typically a pair of, first attachment components 46 and at least onesecond attachmentcomponent 48. More preferably, the closure systemadditionally comprises a primary fastening system 38 such that thediaper 20 has a dual tension fastening system 36. Preferred embodimentsof a diaper having a dual tension fastening system are described incommonly assigned, co-pending, U.S. patent application Ser. No.07/714,476, P&G Case 4412, Well et al., "Absorbent Article WithFastening System Providing Dynamic Elasticized Waistband Fit", filedconcurrently herewith; the specification and drawings of which areincorporated herein by reference.

The dual tension fastening system 36 forms both a side closure and awaist closure. The dual tension fastening system 36 thus comprises aprimary fastening system 38 for providing the side closure and a waistclosure system 40 for providing the waist closure. The primary fasteningsystem 38maintains the first waist region 56 and the second waist region58 in an overlapping configuration such that lateral tensions aremaintained aroundthe circumference of the diaper to maintain the diaperon the wearer. The waist closure system 40 forms a waist closure thatdynamically maintains/creates lateral tensions through the elasticizedwaistband 35 soas to improve the fit and containment characteristics ofthe diaper 20 by reducing gapping, sagging, and rollover of theelasticized waistband 35.

As shown in FIG. 1, the primary fastening system 38 comprises asecurement member 42 disposed adjacent each longitudinal edge 62 in thesecond waist region 58, and at least one landing member 44 disposed inthe first waist region 56 so as to form a portion of the outer surface52. Each securementmember 42 preferably comprises a tape tab 92 and afirst fastening component 112. The landing member 44 preferablycomprises complementary second fastening component 114 engageable withthe first fastening component 112 of the securement member 42. Anexemplary primary fastening system wherein the first and secondfastening components each comprise mechanical closure elementscomprising hook and loop fastening materials is disclosed in U.S. Pat.No. 4,869,724 entitled "Mechanical Fastening Systems With Adhesive TapeDisposal Means For Disposable Absorbent Articles" issued to Scripps onSep. 26, 1989. Primary fastening systems utilizing mechanical closureelements are also disclosed in U.S. Pat. No. 4,846,815 entitled"Disposable Diaper Having An improved Fastening Device"issued to Scrippson Jul. 11, 1989; and U.S. Pat. No. 4,894,060 entitled "DisposableDiaper With improved Hook Fastener Portion" issued to Nestegard on Jan.16, 1990. A primary fastening system having combinationadhesive/mechanical closure elements is described in U.S. Pat. No.4,946,527 entitled "Pressure-Sensitive Adhesive Fastener And Method ofMaking Same" issued to Barttell on Aug. 7, 1990. Each of these patentsareincorporated herein by reference. In a preferred embodiment of thepresent invention as is shown in FIG. 1, the primary fastening system 38comprisesan adhesive tape tab fastening system comprising a tape tab 92having an adhesive attachment layer 96 and a landing member 44comprising a reinforcing strip 116 joined to the backsheet 26. Examplesof such adhesive tape tab fastening systems are disclosed in U.S. Pat.No. 3,848,594 entitled "Tape Fastening System for Disposable Diaper"issued toBuell on Nov. 19, 1974; and the adhesive tape tabs, reinforcingstrip, and indicia means disclosed in U.S. Pat. No. B1 4,662,875entitled "Absorbent Article" issued to Hirotsu and Robertson on May 5,1987. Each of these patents are incorporated herein by reference.

Each securement member 42 of the primary fastening system 38 is intendedtoprovide a fastening means for engaging the landing member 44 so as toprovide a secure, preferably a variable positioning, side closure forthe diaper 20. Thus, the securement member 42 comprises at least onefasteningcomponent. Each securement member 42 also preferably comprisesa means for positioning the fastening component adjacent the landingmember 44 so as to achieve an optimum fitting side closure. Thus, thesecurement member 42may comprise any of the well known configurationsand means for achieving aside closure on a diaper such as (i) a patch orstrip of a fastening component disposed to form a portion of the innersurface of the diaper or(ii) a tape tab having a fastening componentpositioned thereon.

As shown in FIG. 1, each securement member 42 preferably comprises atape tab 92. Any of the well known configurations and constructions of atape tab may be used in the present invention. For example, an exemplarytape tab is described in detail in the hereinbefore referenced U.S. Pat.No. 3,848,594 issued to Buell on Nov. 19, 1974, and which patent isincorporated herein by reference. A particularly preferred tape tab 92hasa fastening surface 98 and a backing surface 99. The fasteningsurface 98 is that surface of the tape tab 92 designed to engage thelanding member 44 of the present invention. Thus, the fastening surface98 of the tape tab 92 is generally oriented to face the inner surface 54of the diaper 20. The backing surface 99 is that surface opposed to thefastening surface 98 and generally faces the outer surface 52 of thediaper 20. The backing surface 99 is thus generally exposed during wearof the diaper 20.

The preferred tape tab 92 is one which is joined to the backsheet 26 ofthediaper 20 to create a fixed portion 93 (i.e., that end of the tapetab 92 joined to the diaper 20 during manufacture). The tape tab 92 hasanother element which is the tab portion 94 (i.e., that end of the tapetab 92 that extends outwardly beyond the longitudinal edge 62 of thediaper 20 and that is grasped by the diaperer in securing the diaper onthe wearer).The distal edge 97 of the tape tab 92 preferably has roundedcorners to eliminate the possibility of harsh corner edges contactingthe wearer's skin so as to prevent stomach red marking. The preferredtape tab 92 of the present invention also comprises a release portion 95joined to the topsheet 24 of the diaper 20. The release portion 95allows the tab portion 94 to be inwardly folded during manufacture toprotect the adhesive attachment layer 96 from contamination ordelamination prior to use. The release portion 95 extends inwardly fromthe longitudinal edge 62of the diaper 20 preferably up to and juxtaposedover a portion of the elastic side panel member 90 so that the loadcarried by the tape tab 92 is transferred into the elastic side panelmember 90 resulting in more effective distribution of the loads (wearingstresses). The tab portion 94is also preferably shorter in the lateraldirection (width) than the release portion 95 so that it is easier forthe diaperer to initially grasp the tab portion 94.

The fastening component of the securement member 42 forms the closurebetween the securement member 42 and the complementary fasteningcomponentof the landing member 44. Thus, the fastening componentprovides a means for engaging the complementary fastening component ofthe landing member 44 to maintain the first waist region 56 and thesecond waist region 58 inan overlapping configuration to provide asecure side closure for the diaper 20. Further, it is preferred that adiaper fit a range of differentsize wearers and that the fasteningsystem be simple and easy to use. Therefore, the fastening componentsshould allow for variable positioning of the zone of closure so that thediaper may fit a range of sizes while also being simple to fasten withminimal effort. The fastening components thus comprise any of the wellknown attachment means for achieving an adjustable positioning secureclosure as defined hereinafter. Examples of such adjustable positioningattachment means include an adhesive attachment layer such as apressure-sensitive adhesive as are known in theart, a mechanical closureelement such as a hook fastening material or a loop fastening material,any cohesive materials as are known in the art, or a combination of anadhesive/mechanical closure element, as hereinafterdescribed withrespect to the waist closure system 40.

The fastening component is disposed on the securement member 42 suchthat it may be a separate member joined to and associated with thesecurement member 42 or a unitary member with the securement member 42.For example, the topsheet 24 or the backsheet 26 may be manufacturedfrom a material that mechanically engages the landing member 44 (thetopsheet 24 or the backsheet 26 being a unitary fastening component).Alternatively, a discrete patch or strip of material may be joined tothe securement member42 (a separate fastening component). Preferably,the first fastening component 112 is a separate material, such as anadhesive attachment layeror a mechanical closure element, positioned onand joined to the tape tab 92. The first fastening component 112preferably comprises an adhesive attachment layer 96 coated on the tabportion 94 to form the fastening surface 98.

In addition, the first fastening component 112 may be positionedanywhere on the securement member 42. For example, the first fasteningcomponent 112 may be positioned in the side panels 72 of the secondwaist region 58 adjacent the longitudinal edges 62. (Exemplary examplesof this construction are shown in U.S. Pat. No. 4,610,682 issued to Koppon Sep. 9, 1986; and in U.S. Pat. No. 3,141,161 issued to Farris on Jul.21, 1964;each of which are incorporated herein by reference.) When thesecurement member 42 comprises a tape tab 92, the first fasteningcomponent 112 is preferably positioned either on all of or at least aportion of the fastening surface 98 of the tab portion 94. The firstfastening component 112 may comprise a combination adhesive/mechanicalclosure element having an adhesive attachment layer and a mechanicalclosure element disposed on another area of the tab portion 94 on thefastening surface 98 and adjacent the distal edge 97 of the tape tab 92.An exemplary embodiment ofthis configuration is disclosed in thehereinbefore referenced U.S. Pat. No. 4,869,724 entitled "MechanicalFastening Systems With Adhesive Tape Disposal Means For DisposableAbsorbent Article" issued to Scripps on Sep.26, 1989, which isincorporated herein by reference.

The landing member 44 of the primary fastening system 38 provides ameans for securing itself to the securement member 42 to provide a sideclosure and to maintain the first waist region 56 and the second waistregion 58 in an overlapping configuration. The landing member 44 may bedisposed anywhere on the diaper 20 so long as it can engage thesecurement member 42 so as to provide the side closure and, preferably avariable positioning side closure. For example, the landing member 44may be disposed so as to form a portion of the outer surface 52 in thefirst waist region 56, so as to form a portion of the inner surface 54in the second waist region 58, or on any other portion or element of thediaper 20 which is disposed to engage the securement member 42. Becausethe landing member 44 determines the approximate location of where thesecurement member 42 should be placed for optimum fit, the landingmember 44 is preferably positioned so as to achieve variable positioningof the side closure so that the diaper may fit a range of sizes, so thatan overlap between the first waist region 56 and the second waist region58 is achieved, and so that when the side closure is formed theattachment components of the waist closure system 40 engage each othersuch that the formation of the side closure also passively fores thewaist closure. The landing member 44 is preferably centered about thelongitudinal centerline67 in the first waist region 56 and extendslaterally outwardly to almost the longitudinal edges 62.

The landing member 44 may either be a discrete, separate element orelements joined to the diaper 20 or a unitary piece of material with anelement of the diaper 20. The landing member 44 may thus comprise, forexample, the topsheet 24 or the backsheet 26. While the landing member44 can assume varying sizes and shapes, it preferably comprises one ormore patches of material joined to the backsheet 26 in the first waistregion 56 that allows for maximum fit adjustment of diaper 20 to thewearer. In apreferred embodiment of the diaper 20 as illustrated in FIG.1, the landingmember 44 has an elongate, rectangular-shape and issecured to the backsheet 26 in the central region 68 of the first waistregion 56 by an adhesive attachment means (not shown) as have beenpreviously discussed. The landing member 44 comprises a fasteningcomponent (second fastening component 114) engageable with the fasteningcomponent of the securement member 42 (first fastening component 112).Thus, the fastening component of the landing member 44 (second fasteningcomponent 114) may be manufactured from a wide range of materials andconfigurations capable of securely engaging the fastening component ofthe securement member 42 (first fastening component 112).

When the first fastening component 112 of the securement member 42comprises an adhesive attachment layer 96, the second fasteningcomponent 114 of the landing member 44 preferably comprises areinforcing strip 116 and/or the backsheet 26. When the first fasteningcomponent 112 of the securement member 42 comprises a mechanical closureelement, the second fastening component 114 also comprises a mechanicalclosure element. Thus,when the first fastening component 112 comprises ahook fastening material,the second fastening component 114 preferablycomprises a loop fastening material.

In a preferred embodiment of the present invention as shown in FIG. 1,the landing member 44 preferably comprises a reinforcing strip 116releasably engageable with the adhesive attachment layer 96 of the tapetabs 92. The reinforcing strip 116 may comprise any of a number ofconfigurations and materials secured to the backsheet 26 of the diaper20. The reinforcing strip 116 is preferably a separate member secured tothe backsheet 26 to form a portion of the outer surface 52 of the diaper20. A preferred reinforcing strip 116 comprises a sheet of biaxiallyoriented polypropylene film.

The reinforcing strip 116 is also preferably provided with indicia means118 for aiding the diaperer in fitting the diaper to a wearer to obtainoptimal waist fit and leg opening fit. The indicia means 118 may be anytype of lines, patterns, ornamental designs, symbols, script, colorcodes,or other markings which have the capability, either inherently orwith additional denotation, to aid an individual fitting the diaper tothe wearer to promptly locate the desired affixation points for aparticular tape tab fastener. Such indicia means 118 are more fullydescribed in U.S.Pat. No. B1 4,662,875 entitled "Absorbent Article"which issued to Hirotsuand Robertson on May 5, 1987 and which isincorporated herein by reference.Indicia means of the present inventionare preferably a combination of different geometric shapes, colors, andobjects such as SESAME STREET or DISNEY characters.

The dual tension fastening system 36 additionally comprises a waistclosuresystem 40 for providing a waist closure adjacent the end edge 64of the diaper 20. The waist closure anchors a portion of the span of theend edge64. Further, when the diaper 20 comprises an elasticizedwaistband 35, the waist closure dynamically creates/maintains lateraltensions through the elasticized waistband 35.

The waist closure anchors a portion of the span of the end edge 64 ofthe diaper 20, preferably a portion of the extensible span of theelasticized waistband 35. (i.e., The first and second attachmentcomponents of the waist closure system 40 act to anchor the positionalrelationship of the elasticized waistband 35 with the elasticized sidepanels 30.) The term "anchor" is used herein to mean that the attachmentcomponents provide an adjustable positioning fastener that achieves aclosure with sufficient shear resistance so that there is little or noshear slippage or movement between the attachment components once theclosure is achieved. The positional relationship of the elasticizedwaistband 35 with the elasticized side panels 30 (i.e., the geometricrelationship between the anchor zones of the first attachment components46) establishes a defined waist circumferential dimension adjacent theend edge 64 of the diaper 20 which is distinct (longitudinally spaced)from the circumferential dimension established by the side closureformed by the primary fastening system 38. This distinct, defined waistcircumferential dimension creates/maintains the required fitdimension(s) at the upper extremities (adjacent the end edge 64) of thediaper 20. Thus, the waist closure system 40 of the present inventioncan also be beneficial for use on diapers not employing an elasticizedwaistband (e.g., a waistshield or a nonextensible waist feature) so asto maintain a nonextensible fit at the end edge 64 (upper edge) of thediaper 20. The anchoring also provides a means for transferring shearforces (tensions) between the elasticized waistband 35 and theelasticized side panels 30 so as to enhance the initial pretensioncreated within the elasticized waistband 35.

The waist closure also creates/maintains lateral tension(s) through theelasticized waistband 35. The waist closure contributes some portion ofaninitial pretension (lateral tension) within the elasticized waistband35 that allows the elasticized waistband 35 to snugly fit against thewearer's waist when initially fitted. The elasticized waistband 35maintains, during use, some portion of the pretension created within itbythe waist closure. Since the elasticized waistband maintains someportion of the pretension created within it, the elasticized waistbandcan repeatedly elastically expand or contract with the motions of thewearer so as to snugly sustain the fit of the diaper against thewearer's waist throughout use. In particular, during wearing conditions,the elasticized waistband, in order to follow the movements of thewearer's waist, may have to contract to its untensioned state (i.e., thepretension goes to zero) however, because the attachment componentsremain engaged, the pretension will be reestablished within theelasticized waistband with further movement and activity by the wearer.(This is in contrast to most conventional elasticized waistbands thatare not pretensioned such as to not be able to further contract todynamically fit the wearer.) This initial pretensioning and maintenanceof the tension thus results in reduced gapping and better sustained fitof the elasticized waistband. Further, the lateral tension(s)created/maintained by the waist closure provide restoring forces withinthe elasticized waistband that reduce or counteract the incidence ofwaistband "rollover". Thus, the waist closure system 40 provides aclosure about the waist of the wearer to improve the initial and dynamicfit and containment characteristics of the diaper in the waist regions.

As shown in FIG. 1, the waist closure system 40 comprises at least one,preferably a pair of, first attachment component(s) 46 and at least onesecond attachment component 48. As shown in FIG. 1, the first attachmentcomponent(s) 46 are longitudinally aligned with the elasticizedwaistband 35 so that the lateral tensions dynamically created/maintainedby the waist closure system 40 extends in and through the elasticizedwaistband 35 during use. Further, the attachment components of the waistclosure system 40 are longitudinally spaced from the securement members42 and thelanding member 44 of the primary fastening system 38 toprovide a distinct,defined waist circumferential dimension for thediaper and two distinct zones of lateral tension(s). The zone of tensioncreated by the primary fastening system 38 secures the garment on thewearer while the zone of tension dynamically created/maintained by thewaist closure system 40 dynamically maintains the upper waist closureduring wear.

At least two anchor zones 122 are created by the attachment componentswhenthe waist closure is formed. These two anchor zones 122 arelaterally spaced from each other with all or at least a portion of theelasticized waistband 35 positioned between the anchor zones 122. Thelateral spacing of these anchor zones can be achieved in a number ofdifferent ways. For example, the lateral spacing between the anchorzones 122 can be fixed by providing the waist closure system 40 with apair of first attachment components 46 laterally spaced from each otherand a second attachment component(s) 48 that allows adjustablepositioning with the first attachment components 46 (e.g., the secondattachment component(s) is relatively wide). In this embodiment, sincethe lateral spacing of the first attachment components 46 is fixed, thelateral spacing of the first attachment components 46 determines andsets the lateral spacing of the anchor zones. In an alternativeembodiment, the waist closure system 40 may comprise a pair of secondattachment components 48 laterally spaced from each other and a firstattachment component(s) 46 that allows adjustable positioning with thesecond attachment components 48 (e.g., thefirst attachment component 46is relatively wide). In this embodiment, the lateral spacing of theanchor zones is determined by the size of the waistof the wearer and theoverall dimension/shape of the diaper since the location of where thesecond attachment components 48 engage the first attachment component(s)46 depends upon the overlap of the side panels in the second waistregion 58 with the side panels in the first waist region 56.

The preferred lateral spacing of the anchor zones 122 is designed toallow passive activation of the waist closure when the side closure isformed, and to assure the maintenance of normal forces applied to thewaist of thewearer to decrease the tendency of the elasticized waistband35 to nonrecoverably rollover while providing an effective amount ofstretch in the elasticized waistband that improves the fit andcontainment of the diaper in the waist. In order to maintain normalforces within the elasticized waistband that provide for recovery of thewaistband and minimize flipping out of the tensioned waistband (i.e.,nonrecoverable rollover), the lateral spacing of the anchor zones woulddesirably be keptto a minimum. However, in order to provide a maximumamount of stretch in the elasticized waistband, the lateral spacing ofthe anchor zones would be desirably chosen to be at a maximum.Therefore, the lateral spacing of the anchor zones is thus chosen so asto balance the need for maintaining the normal forces with the need forproviding an effective amount of stretch in the elasticized waistband.

In the diaper embodiment shown in FIG. 1 that is designed to fitmedium-size (5.4 kg to about 10.8 kg) babies, the lateral spacingbetween the anchor zones 122 (between the first attachment components46) is at least about 25 mm. More preferably, the lateral spacing is atleast about 50 mm. In the embodiment shown in FIG. 1, the lateralspacing of the firstattachment components 46 is most preferably betweenabout 100 mm and about 200 mm. The lateral spacing of the anchor zones122 is determined by measuring the distance from the innermost line ofsecurement (i.e., that line closest to the longitudinal centerline 67)of one anchor zone to the innermost line of securement of the otheranchor zone with the elasticizedwaistband in its contracted state. Thus,in the embodiment illustrated in FIG. 1, the lateral spacing isdetermined by measuring the distance from the innermost edge of one ofthe first attachment components 46 to the innermost edge of the otherfirst attachment component 46.

Each attachment component comprises a fastening means that engages acomplementary fastening means for providing a variable positioning,passively activated, waist closure. As used herein, the term "variablepositioning" closure refers to a fastening system wherein at least oneof the positions of the components can widely vary so as to allow theuser toform i closure at a number of different locations. Thus, forexample, one of the components may have a fixed location on the diaper(e.g., the lateral spacing between the first attachment components 46 isfixed so as to provide for the pretensioning of the elasticizedwaistband 35 and the passive activation of the waist closure) while theother component allows for variable locations of attachment to the fixedcomponent. This is in contrast to a "fixed" positioning closure whichrequires both of the mating elements to be fixed in position such thatthe components must be joined at a specific location each time theclosure is formed (e.g., snapsand buckles). The waist closure system 40also provides a passively activated waist closure. By "passivelyactivated", it is meant that a functional waist closure is achieved withlittle or no additional effort by the diaperer after a suitable initialbody/leg fit (side closure) is achieved using the primary fasteningsystem 38. Passive activation of the waist closure system 40 requiresthe attachment components to not only engage each other so as to providea secure anchor with little or no additional effort but also to bepositioned on the diaper in an arrangement that creates/maintains thelateral tensions within the elasticized waistband 35.

As shown in FIG. 1, the attachment components preferably comprisemechanical closure elements. As used herein, the term "mechanicalclosure elements" describes fastening means which mechanically engageeach other for providing a variable-position closure. Thus, themechanical closure elements may comprise any of the well known means forachieving a variable-position closure by mechanical engagement such asVELCRO or otherhook and loop fastening materials.

When the first attachment component 46 comprises a mechanical closureelement, the second attachment component 48 may comprise "identical"complementary mechanical closure elements or "distinct" complementarymechanical closure elements. As used herein, the term "identical"complementary mechanical closure elements is used to define mechanicalfastening systems wherein the engaging elements of the first componentandthe second component comprise the same configuration or structurethat are interlocking. Examples of such systems are described in U.S.Pat. No. 4,322,875 entitled "Two Strip Materials Used For FormingFasteners" issuedto Brown, et al. on Apr. 16, 1982. The term "distinct"complementary mechanical closure elements is used herein to definemechanical fastening systems wherein the first component is differentfrom the second componentbut is engageable therewith such as a hookfastening material and a loop fastening material. For example, if thesecond attachment component 48 comprises a loop fastening material thenthe first attachment component 46will comprise a hook fastening materialand vice versa.

As used herein, the term "hook fastening material" is used to designatea material having engaging elements. Thus, the hook fastening materialmay also be referred to as a male fastener. It should also be understoodthat the use of the term "hook" should be non-limiting in the sense thatthe engaging elements may comprise any shapes as are known in the art solong as they are adapted to engage a complementary mechanical closureelement such as a loop fastening material or another hook fasteningmaterial.

The hook fastening material is preferably intended to mechanicallyengage fibrous elements of a loop fastening material so as to provide asecure closure. Thus, a hook fastening material according to the presentinvention may be manufactured from a wide range of materials. Suitablematerials include nylon, polyester, polypropylene, or any combination ofthese materials, or other materials as are known in the art. A suitablehook fastening material comprises a number of shaped engaging elementsprotecting from a backing such as the commercially available materialdesignated "Scotchmate" brand No. FJ13402 available from MinnesotaMining and Manufacturing Company, St. Paul, Minn. Alternatively, theengaging elements may have any shape such as hooks, "T's" mushrooms, orany other shape as are well known in the art. An exemplary hookfastening material is described in U.S. Pat. No. 4,846,815 entitled"Disposable Diaper HavingAn Improved Fastening Device" issued to Scrippson Jul. 11, 1989, and whichpatent is incorporated herein by reference.

An especially preferred hook fastening material, as shown in FIG. 1,comprises an array of prongs 120 formed of thermoplastic material. Hotmelt adhesive thermoplastics, in particular polyester and polyamide hotmelt adhesives, are particularly well suited for forming the prongs ofthehook fastening material. The prongs 120 are preferably manufacturedusing amodified gravure printing process by printing the thermoplasticmaterial inits molten state onto a substrate in discrete units, severingthe material in a manner that allows stretching of a portion of thethermoplastic material prior to severance, and allowing the stretchedmolten material to "freeze" resulting in prongs. This preferred hookfastening material and methods and apparatus for making such a hookfastening material are more fully detailed in European PatentApplication 0 381 087; The Procter & Gamble Company; published Aug. 8,1990, which application is incorporated herein by reference.

A loop fastening material provides a plurality of fibrous elements thatengage the engaging elements of a hook fastening material. The loopfastening material may be manufactured from a wide range of materials toprovide fibrous elements, preferably loops. Such suitable materialsinclude nylon, polyester, polypropylene, any combination of thesematerials, or other materials as are known in the art. A suitable loopfastening material comprises a number of fiber loops projecting from abacking such as the commercially available material designated"Scotchmate" brand nylon woven loop No. SJ3401 available from MinnesotaMining and Manufacturing Company, St. Paul, Minn. Another commerciallyavailable loop fastening material comprises a tricot knit fabric havinga plurality of nylon filament loops projecting from a backing of nylonsuch as the commercially available material designated "Guilford No.16110" available from Guilford Mills of Greensboro, N.C. An exemplaryinexpensiveloop fastening material and a method of making such a loopfastening material are described in European Patent Application 0 289198; The Procter & Gamble Company, published Nov. 2, 1988, whichapplication is incorporated herein by reference. A suitable loopfastening material may also be a woven or nonwoven fabric or any othertype of fibrous material or loop material which are well known in theart. Examples of nonwoven materials suitable for use as a loop fasteningmaterial herein are discussed with respect to the materials useful asthe topsheet 24 of the diaper 20. In a preferred embodiment, the loopfastening material is formed by the nonwoven material of the topsheet24.

The attachment components may alternatively comprise an adhesiveattachmentlayer (a layer of adhesive material). Adhesives useful in thepresent invention are preferably pressure-sensitive adhesives formulatedto adhereto a surface at ambient temperature by applying only lightpressure. Particularly preferred adhesives for use herein as theadhesive attachmentlayer are hot melt pressure-sensitive adhesives asare known in the art. Anexemplary hot-melt pressure-sensitive adhesiveis a Kraton based adhesive with tacifiers and other additives such asmarketed by Findley Adhesives, Inc. of Elm Grove, Wis. under thetradename Findley 990 or H-2085.

The attachment components may further comprise a combinationadhesive/mechanical closure element. For example, the attachmentcomponents may comprise a combination fastener such as hook fasteningmaterial and an adhesive attachment layer juxtaposed with the hookfastening material or a mechanical closure element such as a hookfastening material having a layer of adhesive coated over a portion ofthehook fastening material. An exemplary fastener having a combinationmechanical/adhesive system is the pressure-sensitive adhesive fastenerhaving a textured fastening surface such as is disclosed in U.S. Pat.No. 4,946,527 issued to Battrell on Aug. 7, 1990, which patent isincorporatedherein by reference.

The attachment components may alternatively further comprise any othercohesive material or materials that are known in the art for providing avariable positioning fastener capable of being passively activated. Forexample, a cohesive strip or material can be foams, rubbers such ascrepe or latex rubbers, other adhesives, or a high static vinylmaterial. A separable fastener of a high static vinyl material is morefully describedin U.S. Pat. No. 4,979,613 issued to McLaughlin &Kleansmith on Dec. 25, 1990, which patent is incorporated herein byreference.

The attachment components may comprise a separate element joined to thediaper 20 or may be a unitary element with one of the other componentsof the diaper. For example, the topsheet 24 may be manufactured from amaterial (e.g., a nonwoven web), that is capable of mechanicallyengaging the other attachment component (e.g., a hook fasteningmaterial). Further,the backsheet 26 can be formed from a web having atextured pattern with a layer of adhesive coated over a portion of thebacksheet surface to form acombination mechanical/adhesive fastener(attachment component) such as is shown in the hereinbefore referencedU.S. Pat. No. 4,946,527 to Battrell In each of these cases, theattachment component is unitary with another component of the diaper.Alternatively, the attachment component may comprise a discrete strip orpatch joined to the diaper. In a preferred embodiment shown in FIG. 1,each first attachment component 46 comprises adiscrete separate patch ofa hook fastening material joined to the backsheet 26 so as to form aportion of the outer surface 52 while the second attachment component 48is a unitary element comprising a portion of the topsheet 24 in thesecond waist region 58.

In a particularly preferred embodiment of a medium sized diaper, such asthe diaper 20 shown in FIG. 1, the waist closure system 40 preferablycomprises a pair of first attachment components 46. Each firstattachment component 46 comprises an about 12 mm wide (i.e., generallyperpendicular to the longitudinal centerline 67) by about 19 mm patch ofa hook fastening material. The first attachment components 46 arepreferably positioned so as to have a lateral spacing of about 171 mm.Each first attachment component 46 is also spaced longitudinally fromthe end edge 64. If the longitudinal spacing of the first attachmentcomponent (measured from the end edge of the diaper to the closest edgeof the firstattachment component) is too small, the first attachmentcomponent may be too high on the diaper and be in a position to contactthe wearer's skin; if the longitudinal spacing is too great, the firstattachment component may be so low as to allow some rollover of theelasticized waistband. The first attachment components are preferablyspaced from about 3 mm (1/8 inch) to about 15 mm (5/8 inch) from the endedge of the diaper, preferably about 6 mm (1/4 inch). The hook fasteningmaterial used for thefirst attachment components 46 preferably comprisesan array of thermoplastic prongs 120 formed on a backing; the prongs 120of each hook fastening material most preferably being oriented with theengaging means facing inward toward the longitudinal centerline 67 ofthe diaper 20. The waist closure system 40 also comprises a singlesecond attachment component 48 comprising a loop fastening materialformed by a portion of the nonwoven material of the topsheet 24.

The diaper 20 additionally comprises a positioning patch 50 locatedsubjacent the first attachment component 46. The positioning patch 50raises the first attachment component 46 in the Z direction (thickness)toallow the first attachment component 46 to come in better contact withthe second attachment component 48 and allow the waist closure system tomore easily be closed (with less effort). Thus, the waist closure system40 is more effectively passively activated. The positioning patch 50also provides a zone of increased flexural stiffness that reduces thetendency of the flexible ear flaps 88 to fold over onto the firstattachment component(s) 46 thereby occluding the hooks from beingsecured during diaper application. Thus, the positioning patch 50 cancomprise any element that provides a Z direction build up to the firstattachment components 46. As shown in FIG. 1, the positioning patches 50each comprise a rectangular-shaped piece of material positionedsubjacent the first attachment component 46. While the positioningpatches 50 may be positioned directly subjacent the first attachmentcomponents 46, the positioning patches 50 are preferably positionedbetween the topsheet 24 and the backsheet 26. In order to provide aflexurally stiff circumferenceabout the waist of the wearer, the lateraledges of the positioning patchescan be abutted to or slightly overlappedwith the side edges 75 of the elastic waistband member 76. Thepositioning patches 50 preferably comprise a 38 mm wide by 32 mm longpatch of elastomeric foam. More preferably, during manufacture of thediaper, the positioning patches 50 are formed of the same material asthe elastic side panel member 90 with the elastic side panel member 90of one diaper and the positioning patch 50 of the adjacent diaper beingformed from the same segment of material that is then cut after thediaper is completed. Thus, the positioning patch 50 extends from the endedge 64 of the diaper 20 inward toward the center of the diaper 20.

In a preferred embodiment, the diaper also comprises elasticized sidepanels 30 disposed in the second waist region 58. (As used herein, theterm "disposed" is used to mean that an element(s) of the diaper isformed(joined and positioned) in a particular place or position as aunitary structure with other elements of the diaper or as a separateelement joined to another element of the diaper.) The elasticized sidepanels 30 provide an elastically extensible feature that provides a morecomfortableand contouring fit by initially conformably fitting thediaper to the wearer and sustaining this fit throughout the time of wearwell past when the diaper has been loaded with exudates since theelasticized side panelsallow the sides of the diaper to expand andcontract. Further, the elasticized side panels 30 develop and maintainwearing forces (tensions) that enhance the tensions developed andmaintained by both the primary fastening system 38 and the waist closuresystem 40 to maintain the diaper20 on the wearer and enhance the waistfit. The elasticized side panels 30 especially assist in initiallypretensioning the elasticized waistband 35 since the diaperer typicallystretches the elasticized side panels 30 whenapplying the diaper 20 onthe wearer so that when the elasticized side panels 30 contract, tensionis transmitted from the elasticized side panels 30 through the waistclosure system 40 into the elasticized waistband 34. The elasticizedside panels 30 further provide more effective application of the diaper20 since even if the diaperer pulls one elasticized side panel 30farther than the other during application (asymmetrically), the diaper20 will "self-adjust" during wear. While the diaper 20 of the presentinvention preferably has the elasticized side panels 30 disposed in thesecond waist region 58; alternatively, the diaper 20 may be providedwith elasticized side panels 30 disposed in the first waist region 56 orin both the first waist region 56 and the second waist region 58.

While the elasticized side panels 30 may be constructed in a number ofconfigurations, an example of a diaper with elasticized side panelspositioned in the ears (ear flaps) of the diaper is disclosed in U.S.Pat.No. 4,857,067, entitled "Disposable Diaper Having Shirred Ears"issued to Wood, et al. on Aug. 15, 1989, which patent is incorporatedherein by reference. The elasticized side panels 30 may alternatively beformed in anumber of other configurations. For example, U.S. Pat. No.4,381,781 issuedto Sciaraffa, et al. on May 3, 1983, discloses a diaperhaving an elasticized waist in which an elastic member is positioned inan opening in both the topsheet and the backsheet of the diaper suchthat the stretchof the elastic member will not be constrained by thenon-elastic materials.While the Sciaffra et al. patent teaches thecriticality of removing both the topsheet and the backsheet portions ofthe diaper in those areas coinciding with the elastic member, thepresent inventors have learned that satisfactory elastic performance canalso be obtained when only one or when none of the coinciding portionsof the topsheet and the backsheet are removed, especially when theportions of the diaper web containing theelastic member are subjected toan incremental mechanical stretching operation of the type describedhereinafter. A further embodiment of a diaper showing elasticized sidepanels is shown in U.S. Pat. No. 4,938,753issued to Van Gompel, et al.on Jul. 3, 1990. This patent discloses a pant-like garment provided withstretchable side panels formed by attaching discrete stretchable membersto the side edges of the main body of the garment. Thus, the elasticizedside panels 30 of the present invention may comprise a separateelastically extensible material or laminate joined to the diaper. Asshown in FIG. 1, each elasticized side panel 30 preferably comprises anear flap 88 and an elastic side panel member 90 operatively associatedtherewith.

As shown in FIG. 1, each ear flap 88 comprises that portion of the sidepanel 72 that extends laterally outwardly from and along the side edge82 of the absorbent core 28 to the longitudinal edge 62 of the diaper20. Theear flap 88 generally extends longitudinally from the end edge 64of the diaper 20 to the portion of the longitudinal edge 62 of thediaper 20 thatforms the leg opening (this segment of the longitudinaledge 62 being designated as leg edge 106). In a preferred embodiment ofthe present invention, each ear flap 88 in the second waist region 58 isformed by theportions of the topsheet 24 and the backsheet 26 thatextend beyond the side edge 82 of the absorbent core 28.

In a preferred embodiment of the present invention the elastic sidepanel members 90 are operatively associated with the diaper 20 in theear flaps 88, preferably between the topsheet 24 and the backsheet 26,so that the elastic side panel members 90 allow the elasticized sidepanels 30 to be elastically extensible in the lateral direction(laterally elastically extensible). As used herein, the term"elastically extensible" means a segment or portion of the diaper thatwill elongate in at least one direction (preferably the lateraldirection for the side panels and the waistbands) when tensional forces(typically lateral tensional forces for the side panels and thewaistbands) are applied, and will return to about its previous size andconfiguration when the tensional forces are removed.Generally,elastomertc materials useful in the present invention will contractivelyreturn to at least about 75% of their original configurationwithin about5 seconds or less upon stretch and immediate release thereof (i.e., a"snappy" elastic).

The elastic side panel members go can be operatively associated in theear flaps 88 in a number of different ways. For example, the elasticside panel member 90 may be operatively associated in an elasticallycontractible condition so that the elastic side panel member 90 gathersorcontracts the ear flap 88. (A more detailed description of a manner inwhich elastomeric materials may be secured in an elasticallycontractible condition can be found in U.S. Pat. No. 3,860,003 issued toBuell on Jan. 14, 1975, and in U.S. Pat. No. 4,081,301 issued to Buellon Mar. 28, 1978;both patents being incorporated herein by reference.)For example, the elastic side panel members 90 can be contractiblyaffixed in the ear flap 88 by laterally extending the elastic side panelmember 90, joining the elastic side panel member 90 to either or boththe topsheet 24 and the backsheet 26, and allowing the elastic sidepanel member 90 to assume its relaxed or contracted orientation.

Alternatively, the elastic side panel member 90 can be operativelyassociated in an uncontracted state and then treated to contract. Forexample, the elastic side panel member 90 can be formed from materialswhich contract undirectionally and become elastic following specifictreatment such as heating. Examples of such materials are disclosed inU.S. Pat. No. 3,819,401 issued to Massengale, et al. on Jun. 25, 1974and in U.S. Pat. No. 3,912,565 issued to Koch, et al. on Oct. 14, 1975.A moredetailed description of a manner for using a heat-shrinkableelastic memberis described in U.S. Pat. No. 4,515,595 issued to Kievttand Osterhage on May 7, 1985; this patent being incorporated herein byreference. Typically, the topsheet, the backsheet, the elastic sidepanel member, andany other components are secured together while in anuncontracted condition. The laminate is then heated (as with heated air)and the elastic side panel member is allowed to return to its relaxed orcontracted orientation.

In an especially preferred embodiment, the elastic side panel member 90is operatively associated in the ear flap 88 by joining the elastic sidepanel member 90 to the topsheet 24, the backsheet 26, or both while theelastic side panel member 90 is in a substantially untensionedcondition. At least a portion of the resultant composite elastomericlaminate containing the elastic side panel member 90 is then subjectedto mechanical stretching sufficient to permanently elongate the topsheetand the backsheet components (nonelastic components) of the laminate.The composite elastomeric laminate is then allowed to return to itssubstantially untensioned condition. The elasticized side panel is thusformed into a "zero strain" stretch laminate. (Alternatively, theelastic side panel member could be operatively associated in a tensionedconditionand then subjected to mechanical stretching; although this isnot as preferred as a "zero strain" stretch laminate.) As used herein,the term "zero strain" stretch laminate refers to a laminate comprisedof at least two plies of material which are secured to one another alongat least a portion of their coextensive surfaces while in asubstantially untensioned("zero strain") condition; one of the pliescomprising a material which is stretchable and elastomeric (i.e., itwill return substantially to its untensioned dimensions after an appliedtensile force has been released) and a second ply which is elongatable(but not necessarily elastomeric) sothat upon stretching the second plywill be, at least to a degree, permanently elongated so that uponrelease of the applied tensile forces, it will not fully return to itsoriginal undeformed configuration. The resulting "zero strain" stretchlaminate is thereby rendered elastically extensible, at least up to thepoint of initial stretching, in the direction of initial stretching.Examples of such "zero strain" stretch laminates are disclosed in U.S.Pat. No. 2,075,189 issued to Galligan, et al. on Mar. 30, 1937; U.S.Pat. No. 3,025,199 issued to Harwood on Mar. 13, 1962; U.S. Pat. No.4,107,364 issued to Sisson on Aug. 15, 1978; U.S. Pat. No. 4,209,563issued to Sisson on Jun. 24, 1980; and U.S. Pat. No. 4,834,741 issued toSabee on May 30, 1989. Each of these patents are incorporated herein byreference.

Particularly preferred methods and apparatus used for making "zerostrain" stretch laminates out of a topsheet, a backsheet, and anelastomeric member positioned between the same, use meshing corrugatedrolls to mechanically stretch the components. A discussion of suitableapparatus and methods for mechanically stretching portions of a diaperis contained in the hereinbefore referenced U.S. Pat. No. 4,107,364issued to Sisson onAug. 15, 1978 and U.S. Pat. No. 4,834,741 issued toSabee on May 30, 1989. Particularly preferred apparatus and methods aredisclosed in co-pending, commonly assigned, U.S. patent application Ser.No. 07/662,536 entitled "Improved Method And Apparatus For IncrementallyStretching A Zero Strain Stretch Laminate Web To Impart ElasticityThereto"; P&G Case 4339; filed by Gerald M. Weber et al. on Feb. 28,1991; U.S. patent application Ser. No. 07/662,537 entitled "ImprovedMethod And Apparatus For Incrementally Stretching Zero Strain StretchLaminate Web In A Non-Uniform Manner To Impart A Varying Degree ofElasticity Thereto"; P&G Case 4340; filed by Kenneth B. Buell et al. onFeb. 28, 1991; and U.S. patent application Ser.No. 7/662,543 entitled"Improved Method And Apparatus For Sequentially Stretching Zero StrainStretch Laminate Web To Impart Elasticity Thereto Without Rupturing TheWeb"; P&G Case 4341; filed by Gerald M. Weber et al.on Feb. 28, 1991;the specifications and drawings of each one incorporated herein byreference.

Details of a particularly preferred incremental stretching system whichcanbe employed in making "zero strain" stretch laminate elasticized sidepanels of the present invention are set forth in FIG. 8. The fullyassembled diaper web 810 including the "zero strain" side panel web isdirected through the incremental stretching system.

Referring to FIG. 8, the timing of the diaper web 810 containing thesubstantially untensioned elastic side panel members (elastomericpatches 804) is such that the substantially untensioned elastomericpatches 804 substantially coincide with the corrugated or groovedsegments 824 contained on the uppermost corrugated rolls 825 as thediaper web 810 passes between the segments 824 of the uppermostcorrugated rolls 825 and the continuously corrugated or groovedlowermost corrugated rolls 821. In a preferred embodiment of the methodand apparatus, the grooved segments 824 are of greater overall lengththan the elastomeric patches 804, as measured in the machine direction,so as to impart a degree of extensibility to those portions of thetopsheet 24 and the backsheet 26 which are adjacent the elastomericpatches 804 in the diaper 20 (i.e., an extension panel 110 is formed).In addition, the grooved segments 824 preferably are not of sufficientlength to extend into the first waist region of the adjacent diaper,since it is preferable not to impart a degree of extensibility to theportion of the elastomeric patch 804 that will form the positioningpatch 50 of the adjacent diaper.

While the exact configuration, spacing and depth of the complementarygrooves on the uppermost and lowermost corrugated rolls will vary,depending upon such factors as the amount of elasticity desired in the"zero strain" stretch laminate portion, a peak-to-peak groove pitch ofapproximately 0.150 inches, an included angle of approximately 12degrees as measured at the peak, and a peak-to-valley groove depth ofapproximately (0.300) inches have been employed in a particularlypreferred embodiment of the present invention. The exterior peak of eachcorrugation on the aforementioned corrugated rolls typically exhibits aradius of approximately 0.010 inches, while the internal groove formedbetween adjacent corrugations typically exhibits a radius ofapproximately0.040 inches. When the corrugated rolls are adjusted sothat their opposingpeaks overlap one another to a depth between about0.150 and about 0.175 inches, good elastic characteristics have beenproduced in a laminate web of the present invention comprised of 80 milthick elastomertc polyurethane foam patches substantially continuouslybonded on their opposed surfaces to a one mil thick polymeric backsheetand a nonwoven topsheet having a basis weight in the range of about 18to 20 grams per square yard and comprised of polypropylene fibers.

The degree of overlap of the opposing peaks on the aforementionedcorrugated rolls may of course be adjusted, as desired, to produce moreorless extensibility in the resultant "zero strain" stretch laminateweb. Forthe aforementioned roll geometry and laminate web construction,peak-to-peak overlap depths ranging from as little as about 0.050 inchesto as much as about 0.225 inches are feasible.

As can be seen from FIG. 8A, the diaper web 810 is caused by the idlerrolls 872, 874 to wrap the lowermost corrugated rolls 821 sufficientlyto cover the active vacuum ports 822 (shown in FIG. 8) locatedimmediately adjacent each continuous set of grooves 823 on the lowermostrolls 821. The vacuum ports 822, which are positioned so as tosubstantially coincidewith the grooved segments 824 on the uppermostcorrugated rolls 825, are internally connected through the rolls 821 toa pair of vacuum manifolds 826 which exert suction against the diaperweb 810 as the diaper web t s acted upon by the grooved segments 824 ofthe uppermost corrugated rolls 825.

To minimize the build up of either the adhesive used to secure theuntensioned elastomeric patches 804 to the topsheet web 806 and thebacksheet web 805 or the adhesive used to secure the coinciding portionsof the topsheet web and the backsheet web to one another, the groovedsegments 824 on the uppermost rolls 825 and the continuous grooves 823on the lowermost rolls 821 may be either comprised of a low frictionmaterial, such as TEFLON, or coated with a self-lubricating low frictionmaterial such as Permalon No. 503 spray coating, as available from MicroSurface Corporation of Morris, Ill.

The vacuum ports 822 on the lowermost rolls 821 are preferably coveredby aporous material, such as 0.090 inch mesh honeycomb 844, to providesupport to the portions of the diaper web 810 acted upon by the vacuumand to provide a good gripping surface against the web so as tosubstantially prevent lateral slippage or movement of the web across thehoneycomb surface whenever the web is acted upon by the vacuum.

Under optimum circumstances, the maximum degree of incrementalstretching which can be imparted to the "zero strain" portions of theside panel containing the elastomeric patches 804 is determined by thedepth of engagement between the grooves on segments 824 of the uppermostcorrugatedrolls 825 and the continuous grooves 823 on the lowermostcorrugated rolls 821. However, it has been discovered that unless thestretch laminate web is substantially prevented from slipping orcontracting in a direction substantially parallel to the direction ofweb stretching as it passes between the meshing corrugated rolls, theoptimum degree of incremental stretching is not realized. Therefore, inits most preferred form, the incremental web stretching operation iscarried out while the outermost portions of all three layers comprisingthe "zero strain" stretch laminateare subjected to restraint, asgenerally shown in the cross-section of FIG.8B, to substantially preventthe "zero strain" stretch laminate portions ofthe diaper web fromslipping or contracting in a direction parallel to the desired directionof stretching as it passes between the sets of sequentially positionedmeshing corrugated rolls.

However, the present invention may also, if desired, be practiced toadvantage by restraining only the elongatable or drawable layer orlayers of the composite, i.e., it is not an absolute requirement thatthe outermost portions of the elastomertc patches also be restrainedduring the incremental stretching operation. In the latter instance, theelongatable or drawable layer or layers are still permanently elongatedduring the incremental stretching process, but the z-direction bulkingin the resultant "zero strain" stretch laminate web may be somewhat lesspronounced when the stretching tension is removed. This is due to thefactthat the elastomeric patch undergoes a lesser degree of initialstretching during such a process. Accordingly, it can only undergo thissame amount of retraction when it returns to its undistortedconfiguration.

A "zero strain" stretch laminate embodiment of the aforementioned typemay also exhibit some degree of disproportionate localized straining inthe elongatable web or webs, particularly in the areas immediatelyadjacent the opposed edges of the elastomeric patches. In the case of anopaque polymeric backsheet web, these disproportionately strainedportions can become sufficiently thinned that they may even appeartransparent despite the fact that no rupture has taken place. In suchinstances the functionality, (e.g., the imperviousness) of the "zerostrain" stretch laminate portions of the diaper web is not impaired.Embodiments of the latter type are normally employed in situations wherethe aesthetic appearance of the "zero strain" stretch laminate portionsof the resultantdiaper is either hidden from view by the design orconfiguration of the diaper or, if visible, is of no concern to the userof the diaper.

In still another embodiment of the present invention even rupture of oneormore of the elongatable nonelastic webs may not render the resultant"zero strain" stretch laminate web unacceptable for its intended purpose(e.g., rupture of the backsheet web does not necessarily destroy thelaminate web's functionality for its intended purpose as long as one ofthe other plies in the laminate web provides the desired function in thefinished article). For example, some degree of rupturing in theelongatable backsheet web will not destroy the imperviousness of theresultant diaper web if the elastomeric patches also comprise aliquid-impervious material). This is particularly true with respect tothose "zero strain" stretch laminate web embodiments employingsubstantially continuous bonding between the plies in question, sincerelatively close adherence ofthe plies to one another after incrementalstretching renders such ply damage difficult to detect by the end useror the diaperer.

Because the diaper web 810 shown in FIGS. 8-8B is substantiallyimpervious to the passage of air by virtue of the presence of theuppermost backsheetweb 805, the vacuum ports covered by the poroushoneycomb material 844 can,if desired, be employed immediately adjacenteach set of machine direction oriented grooves 823 in the lowermostcorrugated rolls 821. If the elastomeric patches 804 are sufficientlypervious to the passage of air, the suction forces generated by thevacuum will pass through the topsheet web 806 and the elastomericpatches 804 so as to tightly grip the overlying portions of thebacksheet 805. In this instance, all three layers comprising the "zerostrain" stretch laminate portions of the diaper web will be restrainedduring the incremental stretching operation.

If the elastomeric patches were not substantially pervious to thepassage of air, it would be necessary to either (a) position the vacuumports 822 and the overlying honeycomb material 844 just outside theopposed edges ofthe elastomeric patches 804 so that suction forces couldbe exerted on the backsheet web 805 through the topsheet web 806; or (b)restrain all three layers comprising the "zero strain" stretch laminateportions of the diaper web by means of suitable clamping apparatuscapable of acting upon the opposed surfaces of the diaper web.

The suction forces applied to the diaper web 810 shown in FIGS. 8-8B bythevacuum ports 822 acting through the porous honeycomb material 844substantially prevent those portions of the diaper web 810 containingthe substantially untensioned elastomertc patches 804 from slipping orcontracting in laterally inward direction as they pass between themeshingportions of the continuous grooves 823 on the lowermostcorrugated rolls 821 and the grooved segments 824 on the uppermostcorrugated rolls 825.

Because the "zero strain" stretch laminate portions of the diaper web810 containing the elastomeric patches 804 are laterally restrainedthroughoutthe sequential web stretching operation, all portions of the"zero strain" stretch laminate web located intermediate the points ofrestraint are subject to substantially uniform incremental stretching asthe web passes between the continuous grooves 823 on the lowermostcorrugated rolls 821 and the meshing portions of the grooved segments824 on the uppermost corrugated rolls 825.

This not only maximizes the effectiveness of the incremental webstretchingoperation by forcing the elongatable topsheet and backsheetwebs secured tothe elastomeric patches to undergo the fullest possibledegree of elongation during the stretching operation, but alsosubstantially prevents disproportionately high straining of the topsheetand/or backsheet webs to which they are secured in the areas immediatelyadjacentthe opposed peripheral edge portions of the elastomeric patches.

FIG. 9 discloses an alternative incremental web stretching system whichcanbe employed. In the incremental web stretching system shown in FIG.9, a pair of resiliently compressible disks 940 are mounted adjacenteach side of the grooved segments 924 of the uppermost corrugated rolls925. The compressible disks 940 are of a large enough diameter that theytightly grip the diaper web 910 and hold it securely against thecoinciding non-grooved portions of the lowermost corrugated rolls 921 asgenerally shown in the cross-section of FIG. 9A. Like the vacuum portsand the porous honeycomb material in the embodiment of FIG. 8, theclamping effectcreated by the compressible disks 940 and the coincidingnon-grooved portions of the lowermost rolls 921 substantially preventsthe portion of the diaper web 910 containing the elastomertc patches 904from contractingin a direction parallel to the direction of stretchingas the web passes between the meshing corrugated rolls. The FIG. 9embodiment can be used with equal facility on laminate structurescomprised of webs which are either pervious or impervious to the passageof air.

As will be appreciated by those skilled in the art, the foregoingrestraintmethods may be employed either individually or in combinationwith one another to produce the benefits herein described in theresultant "zero strain" stretch laminate portions of the resultantdiaper web.

From the description contained herein, it is clear that the improvedmethodand apparatus may be employed to advantage to produce a wide rangeof diapers either comprised entirely of or including one or morediscrete, isolated "zero strain" stretch laminate web portions.

It is also recognized that while a pair of meshing corrugated rollshaving their corrugations aligned substantially parallel to one anotherare disclosed in the accompanying drawings, the present invention may bepracticed with equal facility employing pairs of corrugated rollswherein the corrugations are not all oriented parallel to one another.Furthermore, the corrugations on such pairs of corrugated rolls need notnecessarily be aligned parallel to either the machine or thecross-machinedirection. For example, if a curvilinear waistband orlegband portion is desired in a single use diaper constructed using the"zero strain" stretchlaminate technology herein disclosed, the meshingteeth on the pairs of corrugated rolls employed to incrementally stretchthe "zero strain" laminate web portions of the diaper web may be arrayedin the desired curvilinear configuration to produce elasticity along thedesired curvilinear contour rather than in a straight line.

It is further recognized that while the preferred processes hereindisclosed employ meshing cylindrical corrugated rolls, the web restraintprinciples may also be carried out utilizing an intermittent stampingoperation employing meshing platens to incrementally stretch the "zerostrain" stretch laminate portions of the web or article in question. Inthe latter instance, the only requirement is that the portions of the"zero strain" stretch laminate web to be incrementally stretched beadequately restrained by suitable vacuum or clamping means before themeshing platens are able to exert enough force on the web to causeslippage or contraction in a direction parallel to the direction ofstretching.

The elastic side panel members 90 can be joined to either the topsheet24, the backsheet 26, or both using either an intermittent bondingconfiguration or a substantially continuous bonding configuration. Asusedherein, an "intermittently" bonded laminate web means a laminate webwherein the plies are initially bonded to one another at discrete spacedapart points or a laminate web wherein the plies are substantiallyunbonded to one another in discrete spaced apart areas. Conversely, asubstantially continuously" bonded laminate web means a laminate webwherein the plies are initially bonded substantially continuously to oneanother throughout the areas of interface. The intermittent bondingconfiguration is normally desirable for "zero strain" laminate webs inthose situations where the substantially inelastic webs in the laminateare relatively elongatable or drawable without rupture and where a highdegree of z-direction bulking is desired in the finished laminate. Acontinuous bonding configuration has generally been found desirable for"zero strain" laminate webs where the degree of z-direction bulking ofthefinished laminate is not of prime importance and one or more of therelatively inelastic webs in the laminate is difficult to elongate ordrawwithout causing rupture. In the latter situation, a substantiallycontinuous bonding configuration maintains all of the layers of thelaminate in relatively close adherence to one another after theincremental stretching operation. Accordingly, even if one or more ofthe relatively inelastic webs is damaged to the point of rupture duringthe incremental stretching operation, the relatively close adherence ofthe damaged portions of the relatively inelastic web or webs to theelastomeric ply makes it difficult for the end user to perceive that anydamage has occurred. Provided that the rupture of the relativelyinelasticweb or webs does not defeat the web's intended functionality,(e.g., imperviousness the damage which does occur to the relativelyinelastic webor webs during the incremental stretching operation isgenerally not perceived as a negative in the end product.

Thus, an unexpected benefit which results from the use of a continuousbonding configuration in particularly preferred "zero strain" stretchlaminate webs is that it permits the manufacturer of the diaper toselect from a much wider range of relatively inelastic webs which may besuccessfully employed in laminates of the present invention In essence,itpermits the use of relatively inelastic webs which would not normallybe considered drawable to any appreciable extent in "zero strain"stretch laminate webs of the present invention Accordingly, unlessexpressly stated otherwise, the term "drawable" as used herein, is notintended to exclude relatively inelastic webs which undergo degree ofthinning or damage-during the incremental stretching operation.

In a preferred embodiment of the present Invention, the elastic sidepanel member 90 is substantially continuously bonded to both thetopsheet 24 andthe backsheet 26 using an adhesive. A glue applicator maybe used to apply a substantially uniform and continuous layer ofadhesive to the backsheet 26 and/or the topsheet 24 in thosepredetermined areas where the substantially untensioned elastic sidepanel member 90 will be placed. In a particularly preferred embodiment,the adhesive selected is stretchable and the glue applicator comprises amelt blown applicating system.

One such melt blown adhesive applicating system which has been found tobe particularly well suited for producing a substantially continuouslybonded "zero strain" stretch laminate web is a melt blown sprayapplicator Model No. GH-50-2-1-GH, as available from J&M Laboratories ofGainesville, Ga. The latter system employs a nozzle having 20 orificesper lineal inch, as measured in the cross-machine direction, eachorifice measuring approximately 0.020 inches in diameter. A FindleyH-2176 Hot Melt Adhesive, as available from Findley Adhesives of ElmGrove, Wis. is preferably heated to a temperature of approximately 340°F. and applied to the backsheet and/or the topsheet at a rate ofapproximately 7.5-10 milligrams per square inch. Heated compressed airat a temperature of approximately 425° F. and a pressure ofapproximately 50 psig isissued through the secondary orifices in theadhesive nozzle to assist in uniformly distributing the adhesive fibrilsduring the laydown operation. The intimate contact of the hot adhesivewith the backsheet 26 for the time which passes prior to the incrementalstretching of the resultant "zero strain" stretch laminate portion ofthe diaper provides softening ofthe backsheet 26. For some webs, such asconventional polyethylene backsheet material, this softening has beenfound beneficial in minimizingdamage to the backsheet during theincremental web stretching process. Thismay be particularly important insituations where the web in question imparts some function, (e.g.,impervious), to the diaper.

Alternatively, the elastic side panel member 90 and any other componentscomprising the "zero strain" portions of the diaper 20 may beintermittently or continuously bonded to one another using unheatedadhesive, heat bonding, pressure bonding, ultrasonic bonding, dynamicmechanical bonding, or any other method as is known in the art.

The elastic side panel members 90 may take on a number of differentsizes, shapes, configurations and materials. For example, theelasticized side panels 30 may be formed from one or a plurality ofelastic side panel members 90 operatively associated in each ear flap88; the elastic side panel members may have varying widths and lengths;or the elastic side panel members may comprise relatively narrow strandsof elastomeric material or a larger area elastomeric patch. Oneelastomeric material which has been found to be especially suitable foruse as the elastic sidepanel member 90 (especially for "zero strain"stretch laminates) is an elastomeric foam having an elongation to breakof at least about 400% and an extension force of about 200 grams perinch of sample width at 50% extension of its unstrained length.Exemplary elastomeric foams which havebeen found suitable for use as anelastic side panel member include: (a) crosslinked natural rubber foamspreferably having a caliper of approximately 50 mils and a density of13.3 pounds per cubic foot (0.214 g/cm³), such as is available fromFulflex Inc. of Middletown, R.I.; or as available from Ludlow CompositesCorporation of Fremont, Ohio and marketed under the tradename Baby Foam;or (b) polyurethane foams having acaliper of approximately 80 mils and adensity of approximately 2.06 poundsper cubic foot (0.033 g/cm³) such asis available from Bridgestone of Yokohama, Japan and marketed under thetradename Bridgestone SG polyurethane foam; or as available from GeneralFoam of Paramus, N.J. and marketed under the designation of PolyurethaneFoam No. 40310. Other suitable elastomeric materials for use as theelastic side panel members 90 include "live" synthetic or naturalrubber, other synthetic or natural rubber foams, elastomertc films(including heat shrinkable elastomeric films), elastomeric scrim,elastomeric woven or nonwoven webs, elastomericcomposites such aselastomertc nonwoven laminates, or the like.

As shown in FIG. 1, the elastic side panel member 90 comprises a patchof elastomeric material (elastomeric patch) that preferably extendsthrough amajority of the length of the ear flap 88 in the second waistregion 58. When the diaper is manufactured, the elastomeric patch ispreferably positioned so that it forms not only the elastic side panelmember 90 of one diaper but also the positioning patch 50 in the firstwaist region 56 of the adjacent diaper. Thus, registry problems insecuring the elastic side panel members to the diaper at high speed,such as disclosed in the previously referenced Wood, et al. patent, areeliminated. Thus, the elastic side panel member 90 preferably extendsfrom the end edge 64 of the diaper 20 inward toward the leg edge 106 ofthe ear flap 88. The length and width of the elastic side panel members90 are dictated by the diaper's functional design.

While the elastic side panel member 90 may longitudinally extend throughthe entire length of the ear flap 88, it is preferred that the elasticside panel member 90 extend through only a portion of the length of theear flap 88 so as to form an extension panel 110. As shown in FIG. 1,the extension panel 110, the portion of the elasticized side panellongitudinally extending from the base edge 108 of the elastic sidepanel member 90 to the leg edge 106 of the ear flap 88, has also beenmechanically stretched at least to a degree to be extensible (i.e., thematerials that make up the extension panel 110 have been prestrained orpermanently elongated). This "prestrained" extension panel allows thisportion of the elasticized side panel to effectively elongate (yield)whenthe "zero strain" stretch laminate portion of the elasticized sidepanel isextended, without generating excessive tension forces near theleg regions of the wearer that could cause skin irritation or redmarking in the legs.(i.e., Without the "prestrained" extension panel,tensional forces would beconcentrated along a line through the extensionpanel 110 when the elasticized side panel is extended that could indent,rub, or chafe the skin of the wearer.) While there are a number of waysto prestrain the extension panel 110 of the elasticized side panels 30,the extension panel110 is preferably prestrained in the same manner asthe mechanical stretching performed on the "zero strain" stretchlaminate portion. While the extension panel 110 of the elasticized sidepanels 30 may be formed from a number of different materials, in thepreferred embodiment shown inFIG. 1, the extension panel 110 is formedfrom the portions of the topsheet24 and the backsheet 26 forming the earflap 88.

It has been found that the extension characteristics including theextension forces, extension modulus, and available stretch (extension);and the contractive forces; elastic creep; elastic hysteresis; and rateofcontraction of the elasticized side panels 30 are importantconsiderations in the performance of both the elasticized side panels 30and the diaper 20. The extension characteristics give the diaperer andwearer the overallperceived "stretchiness" during use. They also effectthe ability of the diaperer to achieve a suitable degree of applicationstretch (i.e., for a "normally" perceived tensioning of the diaperduring application, the total amount of resultant stretch is thatdesired to achieve/maintain goodconformity of fit). An elasticized sidepanel with a relatively high extension modulus can cause red marking onthe wearer's skin while a relatively low extension modulus can causesagging/slipping on the wearer.Elasticized side panels having too littleavailable stretch may not achievea suitable level of body conformity andmay contribute in making the diaperuncomfortable to wear and hard todon. A diaper having elasticized side panels with very low contractiveforces, or poor elastic creep or elastic hysteresis may not stay inplace on the wearer and may tend to sag/slip onthe wearer resulting inpoor fit and containment.

For the elasticized side panels 30 of the present invention, it has beenfound that the extension characteristics of extension force andextension modulus are preferably within defined ranges. The extensionforce preferably is greater than or equal to about 250 grams_(f). It ispreferred that these extension forces be generated at extensions betweenabout 0.25 inches (6.25 mm) and about 1.25 inches (31.25 mm). For themostpreferred embodiments, the elasticized side panels preferably havean extensional force between about 250 grams_(f) and about 500 grams_(f)at an extension of between about 0.25 inches (6.25 mm) and about 0.75inches (18.75 mm).

Available stretch measures the maximum amount of material available inthe elasticized side panels to reversibly stretch to conform to thewearer's body during wear. Thus, the amount of available stretch relatesto the maximum amount of extension that the diaperer has available tofit the diaper to the wearer. In addition, the maximum amount ofrecoverable extension available for the diaper to comply with wearer'sbody. The available stretch is calculated from the equation: ((stretchedlength-original length)-original length)×100. The minimum amount ofavailable stretch required for a diaper application using elasticizedsidepanels is preferably an available stretch of at least about 35% formedium sized diapers and at least about 50% for large sized diapers.

The amount of sustainable contractive force (tension) exerted by theelasticized side panel on the wearer is an important property of theelasticized side panel. An elasticized side panel with insufficientcontractive forces may result in the diaper slipping down after beingwornand loaded. Excessive contractive forces may reduce the comfort forthe wearer and produce pressure markings on the wearer's skin.Contractive force is measured as the force per unit width produced whilerelaxing an elastomertc composite at a particular extension. Inpreferred embodiments of the present invention, the contractive force ofthe elasticized side panels is preferably at least about 90 grams/inchat 50% extension (a 50% extension would require the sample to bestretched to 1.5 times its original length).

Typical elastomeric materials show a hysteresis loop of force in theirstress-strain property. That is, for a given extension, the force(extension force) required to uniaxially extend the elastomeric materialis greater than the force (contractive force) the elastomeric materialexerts when it is allowed to contract from its pre-extended condition.Theformer curve can be referred to as the "load curve" and the lattercurve can be referred to as the "unload curve". The "load" extensionforce (extension force) is felt by the diaperer when the elasticizedside panel is stretched to apply the diaper to the wearer. The wearermore nearly "feels" the "unload" contractive forces (contractive forces)once the diaper is on. Therefore, the hysteresis loss should not be sogreat that the contractive force is low enough to allow sagging/slippingof the diaper on the wearer.

All elastomeric materials undergoing sustained stress/strain havediminishing forces with time (i.e., elastic creep). Therefore, it isdesired to make sure this reduction in wearing forces over time doesn'tfall below a minimum for wearing stability. The elastic creep shouldtherefore be kept at a minimum. In preferred embodiments of the presentinvention, the final length of the elastomeric material is not greaterthan about 1.2 times the original length under tension for 30 minutes.

The extension forces and available stretch of the elasticized waistband35 can be important considerations in the performance of both theelasticizedwaistband 35 and the elasticized side panels 30. While theextension forcesof the elasticized waistband 35 may be greater than theextension forces ofthe elasticized side panels 30, in a preferredembodiment of the present invention the extension forces of theelasticized waistband 35 at its designed extensions is less than orequal to the extension forces of each elasticized side panel 30 at itsdesigned extensions. An elasticized waistband 35 having lower extensionforces than that of the elasticized side panels 30 provides for easystomach movement without displacing the diaper on the child. The higherextension force elasticized side panels allow for small dimensionalchanges over the hip and under the stomach to keep the productcomfortably in tension on the wearer. This design provides better fit,less leakage and improved comfort for the wearer through the reductionof sagging, gapping, rollover and roll-in at the front of the diaper andoverall sliding/slipping of the diaper or diaper absorbent core on thewearer during use. As discussed herein, FIG. 6 discloses an alternativeembodiment of the present invention wherein the shaped "expansive rummypanel" preferably has lower extension forces [and/or higher availablestretch] than the elasticized side panels to provide the improvedperformance discussed herein.

The elasticized side panels 30 may also be provided with differentialextensibility along the longitudinal axis when stretched in the lateraldirection. As used herein, the term "differential extensibility" is usedto mean a material having a nonuniform degree of elastic extensionalproperties, as measured in the direction of stretching at various pointsalong an axis oriented substantially perpendicular to the direction ofstretching. This may, for example, include varying the elastic modulusor available stretch or both of the elastomeric material(s). Thedifferentialextensibility is preferably designed into the elasticizedside panels 30 sothat the lateral extensibility varies longitudinallythrough at least a portion of the elasticized side panel as measuredfrom the end edge 64 of the diaper 20 to the leg edge 106 of the earflap 88. Without wishing to be bound by any theory, it is believed thatdifferential extensibility along the longitudinal axis when stretched inthe lateral direction allowsthe elasticized side panel to differentiallystretch and conform to the wearer's waist during use while providing asecure anchor about the hip ofthe wearer so as to promote sustained fitand reduce leakage at the waist and legs. Such a configuration may allowmore "expansion" in the hip area to accommodate changes in the wearer'sbody size as the wearer moves and changes positions (standing, sitting,lying). In an alternative embodiment, a degree of reduced lateralextensibility in the portion of the elasticized side panel adjacent tothe end edge 64 of the diaper 20 requires more of the total extension tobe assumed by the elasticized waistband 34 thereby resulting in morelocalized stretching of the elasticized waistband 34 and a morecompliant abdominal fit.

The differential extensibility can be achieved in a number of differentways. The elasticized side panels 30 can have multiple combinedelastomeric materials, multiple configurations for the elastomericmaterials, or the extension properties of the elastomeric or othermaterial or materials making up the elasticized side panel may benonuniform. For example, differential extensibility can be achieved inselected adjacent portions of the elasticized side panel by usingelastomeric materials having varying extension or contractive forces,modulus, or other inherent properties such that more or less (varying)lateral extensibility is achieved in one portion of the elasticized sidepanel than the adjacent portion. The elastomeric materials may also havevarying lengths, sizes, and shapes that provide differentialextensibility. Other ways of varying the properties of materials thatformthe elasticized side panels as are known in the art may also beused.

A particularly preferred method and apparatus for imparting a varyingdegree of extensibility to a "zero strain" stretch laminate is to passthe "zero strain" stretch laminate through at least one set of meshingcorrugated rolls, at least one of the corrugated rolls havingcorrugationsof nonuniform profile along its point or points of contactwith the "zero strain" stretch laminate web. As a result, the portionsof the laminate web passing between the set of rolls are nonuniformlystretched. This, in turn, produces a "zero strain" stretch laminatewhich is nonuniformly elasticized in a direction substantiallyperpendicular to the nonuniformlyprofiled corrugations.

The diaper 20 is preferably applied to a wearer by positioning one ofthe waist regions, preferably the second waist region 58, under thewearer's back and drawing the remainder of the diaper between thewearer's legs so that the other waist region, preferably the first waistregion 56, is positioned across the front of the wearer. The tabportions 94 of the tapetabs 92 are then released from the releaseportion 95. The diaperer then wraps the elasticized side panel 30 aroundthe wearer, while still grasping the tab portion 94. The elasticizedside panel 30 will typically be extended and tensioned during thisoperation so as to conform to the size and shape of the wearer. Thefirst fastening component 112, the adhesive attachment layer 96, issecured to the second fastening component114 of the landing member 44 toeffect a side closure. In the preferred embodiment of the presentinvention when the side closure is formed, the waist closure is also"automatically" formed, i.e., the waist closure is passively activated.The waist closure is formed by the engagement of the first attachmentcomponents 46 with the second attachment component 48. With theformation of the waist closure, the elasticized waistband 35 ispretensioned so as to provide the fit and containment benefits describedherein.

As shown in FIGS. 4A-4D, the elastic waist feature 34 of the presentinvention moves with and conforms to the waist of the wearer as thewearersits, stands, or moves such that the end edge is in the samegeneral relation with respect to the navel of the wearer when the wearerstands, sits, or stands after sitting. Therefore, the discussion thatfollows relates the relative motions in relation to the navel. As shownin FIG. 4A, the waistline panel zone 138 contacts the waist of thewearer and snugly fits against the waist as a result of the tensioninduced in the elasticized waistband by the closure system as initiallyapplied. As shownin FIG. 4B, as the wearer begins to sit down, theinterconnecting panel zone 130 pivots about the first flexural hingezone 132 and about the second flexural hinge zone 134 to move theelasticized waistband out of the plane that it was originally in. Thewaist edge of the absorbent core tends to move to sit down, theabsorbent core is pushed further toward thenavel while theinterconnecting panel zone 130 tends to flex and fold aboutthe absorbentcore. The stomach of the wearer also begins to push outwardlytoflexurally deflect the waistline panel zone 138 in relation to theshaping panel zone 136 about the predisposed waistband flexural hingezone140. As shown in FIG. 4D with the wearer completely sitting down,the absorbent core has pushed to its furthest extent against the bellywith the interconnecting panel zone 130 totally flexed against the innerportion of the absorbent core. The shaping panel zone 136 is flexurallydeflected to be in contact with the inner portion of the stomach whilethewaistline panel zone 138 has been completely pushed and flexurallydeflected about the predisposed resilient waistband flexural hinge zone140 to conform to the protruding waist of the wearer. Thus, a snug fitbetween the elasticized waistband and the wearer's waist is maintained.Asthe wearer stands up from sitting down, the process is repeated inreverse order with the resiliency of the waistband flexural hinge zoneproviding arestoring force/moment that allows the waistline panel zone138 to maintaincontact with the waist of the wearer as the wearercontinues to stand up, and to return the shaping panel zone 136 and thewaistline panel zone 138 to their previous in-use (pretensioned)configuration against the waist with friction finally pulling theinterconnecting panel zone 130 up into generally its original positionwith intimate contact between the elasticized waistband and the waist ofthe wearer. After several wearing cycles, a condition similar to thatshown in FIG. 4B becomes the "neutral"position during standing, then allfurther movements of the wearer resemblethe cycle shown in FIGS. 4Bthrough 4D.

FIG. 5 shows an alternative construction for the elasticized waistbandof the present invention. The elasticized waistband 535 comprises aportion of the backsheet 26, preferably prestrained; a portion of thetopsheet 24;and an elastic laminate comprising an elastomeric member 76and a facing member 501. The elastomeric member 76 is positioned betweenthe backsheet 26 and the facing member 501 with the topsheet 24 beingpositioned betweenthe backsheet 26 and the elastomeric member 76. Theelasticized waistband 635 is preferably formed by manufacturing thediaper with the topsheet 24 and the backsheet 26 joined together,forming a bi-laminate of the elastomertc member 76 and the facing member501 in a separate step, and subsequently joining the bi-laminatematerial to the topsheet 24 of the combination topsheet/backsheet withthe elastomertc member 76 facing the topsheet 24 so that the facingmember 501 contacts the skin of the wearer.In this embodiment, theelastomeric member 76 is preferably a heat-shrinkable elastomericmaterial as previously described herein. The facing member 501 ispreferably a soft, non-irritating material such as the materialspreviously described with respect to the materials suitable for use asthe topsheet 24. The facing member 501 is preferably a nonwovenmaterialsimilar to the nonwoven material preferred for use as the topsheet

FIG. 5A shows a further alternative construction of the elasticizedwaistband of the present invention. The elasticized waistband 535 isformed from a portion of the backsheet 26, preferably prestrained; afacing member 501; an elastomeric member 76 positioned between thebacksheet 26 and the facing member 501; a portion of the topsheet 24positioned between the backsheet 26 and the elastomertc member 76; and aresilient member 77 positioned between the topsheet 24 and theelastomericmember 76. The elasticized waistband 535 is preferably formedfrom the samematerials as previously discussed and in the same manner asdiscussed with respect to the embodiment shown in FIG. 5, except that atri-laminate of the facing member 501, the elastomeric member 76, andthe resilient member77 is formed and then secured to the topsheet 24.

FIG. 6 shows an alternative embodiment of the diaper and the elasticwaist feature of the present invention. The elastic waist feature 634comprises a relatively high edge compression stiffness interconnectingpanel zone 130 flexurally joined to the containment assembly 22; an"expansive rummy panel" elasticized waistband 635 flexurally joined tothe interconnecting panel zone 130; a first flexural hinge zone 132flexurally joining the interconnecting panel zone 130 with thecontainment assembly 22; and a second flexural hinge zone 134 flexurallyjoining the elasticized waistband 635 with the interconnecting panelzone 130. As shown in FIG. 6,the elasticized waistband 635 has a deep"pentagon" shape to form an "expansive tummy panel". The elasticizedwaistband is longer (longitudinaldimension) to provide for the primaryside closure to be formed below the area of stomach movement. Thelongest dimension of the elasticized waistband 635 (as measured from theend edge 64 longitudinally inward) is preferably between about 38 mm(1.5 inches) and about 88 mm (3.5 inches), more preferably between about50 mm (2.0 inches) and about 57 mm (2.25 inches) for medium-sizeddiapers. This shape provides a waistband that moves and expands with thewearer's stomach as well as differential lateral extensibility such thatportions of the elasticized waistband adjacent the end edge 64 are moreextensible than adjacent portions farther from the end edge 64. Theelasticized waistband 635 comprises a shaping panel zone 136; awaistline panel zone 138; and a predisposed, resilient, waistbandflexural hinge zone 140. The waist edge 83 of the absorbent core 28 isgenerally parallel to the end edge 64 of the diaper (a straight line)and is moved longitudinally farther away from the end edge 64 to providefor the deeper "expansive tummy panel". (In medium-sized diapers, thewaist edge 83 of the absorbent core 28 is preferably positioned betweenabout 50 mm (2 inches) and 57 mm (about 2.25inches) longitudinally awayfrom the end edge 64.) The diaper embodiment shown in FIG. 6additionally comprises a modified shape landing member 644of the primaryfastening system, longitudinally longer first attachment components 646disposed on the backsheet 26, and a laterally wider positioning patch650 positioned subjacent each of the first attachment components 646.

The elasticized waistband 635 is preferably constructed of a portion ofthebacksheet 26, a portion of the topsheet 24, an elastomeric member 76positioned between the topsheet 24 and the backsheet 26, and a resilientmember 77 positioned between the backsheet 26 and the elastomeric member76. The elastomeric member 76 preferably comprises an elastomertc foamwhile the resilient member 77 comprises a nonwoven layer such as hasbeen previously described herein. The bi-laminate elastomertc materialof the elastomeric member 76 and the resilient member 77 preferablyextends beyond the mechanically stretched edges of the elasticizedwaistband 635 and forms a portion of the interconnecting panel zone 130and a portion ofthe containment assembly 22 since it preferably extendslongitudinally inwardly beyond the waist edge 83 of the absorbent core28. The overlap ofthe bi-laminate elastomeric material with theabsorbent core 28 is designedto stiffen the interconnecting panel zone130 and to reduce the potential for roll-over of the elasticizedwaistband 635 in this embodiment. (In a preferred medium-sized diaper,the overlap between the elastomeric material and the absorbent core isbetween 0 mm to about 6 mm (1/4 inch)).The elasticized waistband 635preferably comprises a stretch laminate so that the elasticizedwaistband is capable of expanding beyond the originalplanar state of thediaper. The elasticized waistband 635 is preferably manufactured bysecuring the elastomeric material between the topsheet andthe backsheet(most preferably in a tensioned condition), and mechanically stretching(as hereinbefore described with respect to the elasticized sidepanels)the portion of the elastic waist feature in the shape desired to formthe elasticized waistband. (i.e., the grooves and lands of thecorrugated rolls correspond to the desired pentagon shape of theelasticized waistband.) This stretch laminate (preferably themechanicallystretched, pretensioned, stretch laminate) allows forexpansion of the elasticized waistband well beyond the dimensions of thecircumference of the diaper formed by the primary closure system andbeyond the initial dimension of the end edge 64 (beyond the planar stateof the diaper itself). (i.e., The elasticized waistband is capable ofexpanding well beyond the dimension of the circumference of the fixeddimension of the side closure (even beyond the dimension of thematerials initially formingthe diaper) so as to follow the wearer'sstomach movements.) This expansioncan also be accomplished by orenhanced (for stretch laminates) by "windowing" the elastic waistfeature.

In this embodiment, the interconnecting panel zone 130 is relativelystiff and has a higher edge compression stiffness than the shaping panelzone 136 and the waistline panel zone 138. (Thus, this elastic waistfeature functions differently than as shown in FIG. 4A-4D. ) Thisrelative stiffness of the interconnecting panel zone 130 furtherenhances the ability of the elasticized waistband 635 to expand beyondthe dimensions of the primary side closure. The interconnecting panelzone 130 preferablycomprises a portion of the topsheet 24, a portion ofthe backsheet 26, a portion of the elastomeric material comprising theelastomeric member 76 and the resilient member 77, and a portion of thelanding member 644 sincethe shape of the landing member 644 has beenmodified so as to conform to the shape of the elasticized waistband 635.The landing member also extends beyond the waist edge 83 of theabsorbent core 28 to form a portion of the containment assembly 22. Thelanding member 644 preferably extends well beyond the waist edge 83 ofthe absorbent core 28 to allow lower taping of the primary closuresystem so as to position the primary side closure (the primary tensionline) below the area of stomach movement(i.e., below the lowermost pointof the elasticized waistband). The top edge (the edge closest to the endedge) of the tape tab has also been longitudinally positioned fartherfrom the end edge to accomplish this lower taping. The tape tab ispreferably longitudinally positioned about 39 mm (about 1.56 inch) fromthe end edge in a preferred medium-sized diaper.

The shaping panel zone 136 of the elasticized waistband 635 comprises aportion of the backsheet 26, a portion of the topsheet 24, a portion ofthe elastomertc member 76, and a portion of the resilient member 77. Thewaistline panel zone 138 comprises a portion of the topsheet 24, aportionof the elastomeric member 76, and a portion of the resilientmember 77. Thewaistline panel zone 138 does not comprise a portion ofthe backsheet 26 since it has been removed in this region. Thepredisposed, resilient, waistband flexural hinge zone 140 is formed bythe structural discontinuity caused by the removal of the backsheet inthe waistline panel zone 138 (a "windowed" elasticized waistband).

The window is at least about 4.5 mm (about 3/16 inch), preferably fromabout 9 mm(about 3/8 inch ) to about 16 mm(about 5/8 inch ), long andabout 125 mm (about 5 inches) wide for preferred medium-sized diapers.Thewaistline panel zone 138 is thus able to flexurally bend and deflectabout the area where the backsheet has been removed. (In an alternativeembodiment, the backsheet need not be removed but the pattern of bondingof the materials together would create the predisposed, resilient,waistband flexural hinge zone.) Thus, with the removal of the backsheet,the edge compression stiffness (and the extension forces) of thewaistlinepanel zone is less than the edge compression stiffness (and theextension forces) of the shaping panel zone. As previously discussed,the edge compression stiffness of the shaping panel zone is less thanthe edge compression stiffness of the interconnecting panel zone. It hasbeen foundthat the edge compression stiffness of the waistline panelzone is preferably less than about 100 grams_(f), more preferablybetween about 20 grams.sub. f and about 50 grams_(f), most preferablyabout 35 grams_(f) with the edge compression stiffness of the shapingpanel zone being preferably greater than that of the waistline panelzone, most preferably about 50 grams_(f). The bending flexure restoringforce of the waistband flexural hinge zone, and preferably the entireelasticized waistband, is greater than about 20 grams_(f), morepreferably between about 40 grams_(f) and about 80 grams_(f), mostpreferably about 60 grams_(f).

Based upon the materials used and the manner of constructing theelasticized waistband, the extension forces at its designed "in-use"extensions are less than or equal to the extension forces of eachelasticized side panel at their designed "in-use" extensions. Theextension forces of the elasticized waistband are less than theextension forces of the elasticized side panels to allow the stomach tomove more with the elasticized waistband as previously discussed herein.Further, the available stretch of the elasticized waistband is typicallygreater than the available stretch of the elasticized side panels. Forpreferred diapers, the extension forces of the elasticized waistband arepreferably less than or equal to about 250 grams_(f) at extensions ofbetween about25 mm (1 inch) and about 76 mm (3 inches), more preferablybetween about 25mm (1 inch) and about 50 mm (2 inches). Most preferably,the extension forces for the elasticized waistband are between about 75grams_(f) and about 250 grams_(f) at 25 mm (1 inch) to about 76 mm (3.0inches) extensions, more preferably between about 25 mm (1 inch) andabout 50 mm (2 inches). Since in a preferred embodiment of the elasticwaist feature, a segment of the backsheet has been removed to form thewaistline panel zone, the extension forces of the waistline panel zoneare less than the extension forces of the shaping panel zone. (The edgecompression stiffness is also changed by this windowing.) The extensionforces of the waistline panel zone are preferably between about 75grams_(f) and about175 grams_(f) at these designed "in-use" extensionsfor the elasticized waistband while the extension forces of the shapingpanel zone are preferably between about 175 grams_(f) and about 225grams_(f) at these extensions. Most preferably, the extension force ofthe elasticized waistband in the waistline panel zone is about 150grams_(f) at a 50 mm (2 inch) extension and in the shaping panel zone isabout 200 gram_(f) at a 50 mm (2 inch) extension. This is in contrast tothe extension forcesof the elasticized side panels wherein it is desiredthat the elasticized side panels have an extension force window ofgreater than or equal to about 250 grams_(f) at extensions of betweenabout 6 mm (0.25 inches) and about 76 mm (3 inches), more preferablybetween about 250 grams_(f) to about 500 grams_(f) at extensions ofbetween about 6 mm (0.25 inches)to about 19 mm (0.75 inches).

The positioning patch 650 is disposed in the diaper so as to abut withor extend beyond the side edge 75 of the elastomeric member 76 of theelasticized waistband 635. The positioning patch 650 preferablycomprises the same elastomeric foam material as is used for theelastomeric member 76. In fact, the positioning patch 650 can comprise aportion of the elastomertc member 76 if desired. This disposition forthe positioning patch adds additional stiffness in the first side panels70 to provide a more secure and stiffer panel that decreases the foldingof the first sidepanel 70 at the crease between the elastomeric member76 and the positioning patch 650. In a preferred embodiment of amedium-sized diaper,the positioning patch overlaps the elastomertcmember from 0 mm to about 3.1 mm (1/8 inch).

The first attachment components 46 of the embodiment shown in FIG. 6 arepreferably longer in the longitudinal direction because of the preferredshape of the elasticized waistband, because of the desire to pretensiona greater area of the deeper elasticized waistband, and because of thepreferred lower securement of the primary fastening system. In apreferredembodiment for medium-sized diapers, the first attachmentcomponents are preferably about 25 mm (about 1 inch) long.

FIG. 7 shows an alternative embodiment of the elastic waist featureshown in FIG. 6. As shown in FIG. 7, the shape of the waist edge 783 ofthe absorbent core 28 has an arcuate shape. The arcuate shape absorbentcore has ears 700 which extend upwardly beyond the elasticized waistband735 tobound a portion of the elasticized waistband and to furtherstiffen the areas adjacent the elasticized waistband 735 and provideadditional containment.

In a further alternative embodiment, the elasticized waistband is formedsimilarly to that shown in FIG. 2 except that the resilient membercomprising a nonwoven material is interposed between the topsheet andthe elastomertc member rather than between the backsheet and theelastomeric member as shown in FIG. 2.

An alternative embodiment of an elastic waist feature additionallycomprises a waistcap feature. Such a waistcap feature is disclosed inU.S.Pat. No. 4,734,246 issued to Lawson on May 10, 1988 and in U.S.patent application Ser. No. 07/571,000, allowed, Robertson, filed onAug. 21, 1990; each of which are incorporated herein by reference. Thewaistcap would be formed as an extension of the elastomeric material orelastomericlaminate forming the elasticized waistband. The elastic waistfeature wouldthus additionally comprise a waistcap zone extendinglongitudinally inward from the waist edge of the absorbent core. Thewaistcap zone would comprise a barrier member having a proximal edgejoined to the containmentassembly (preferably the topsheet) adjacent thewaist edge and a distal edge capable of being spaced away from (Zdirection) the absorbent core toprovide a channel to contain bodyexudates.

FLEXURE BENDING TEST

The flexure bending test uses an INSTRON Model 4502 as available fromInstron Corporation of Canton, Mass. a special displacement "T-rod", andaspecial test sample holder. As shown in FIG. 11, the "T-rod" 1101comprisesa pair of 1/4 inch (6.35 mm) diameter metal rodsperpendicularly mounted together, Preferably, the end of the drive rod1102 (the longer of the rods, being about 125 mm (about 5.25 inches)) istapered to fit the circumference of the push rod 103 (the shorter of therods, being about 75mm (about 3 inches)) and the two are glued, weldedand/or screwed to each other. The opposite end of the drive rod 102 ismounted to the crosshead unit of the INSTRON. The test sample holder 104comprises a fixture base 105 to position and support the supporting rods108. The fixture base 1105comprises a base 106 and two rectangularsupports 107 mounted in parallel on the base 106. The base 106 and thesupports 107 are each preferably made of LEXAN (plexiglas) plate ofabout 1/2" to 3/8" thickness. A supporting rod 108 (same material as the"T-bar" and about 150 mm (about 6inches) long) is mounted on eachsupport 107 of the fixture base 105. The supporting rods 108 are mountedso as to be spaced 16 mm apart, center-to-center. As shown in FIG. 11,the "T-rod" 1101 is centered between the supporting rods 108.

The INSTRON is set for a crosshead speed of 20 mm/min, a chart speed of400mm/min, and with full scale at 500 grams_(f). The INSTRON is set upso that the crosshead unit will travel 6 mm down and back, with thechart to follow the crosshead unit down and back.

As shown in FIG. 10, the sample 1000 to be tested is taken from theelasticwaist feature 34 so that the waistband flexural hinge zone 140 ispreferably centered within the sample 1000, although some samples maynot have the waistband flexural hinge zone centered, The sample 1000 isat a minimum 16 mm long (longitudinal direction), preferably 25 mm orany length available, and 50 mm wide (lateral direction.) As shown inFIG. 11,the sample 1000 is centered on the supporting rods 1108 so thatthe waistband flexural hinge zone 140 will be directly under the T-rod1101. The outer surface of the sample 1000 (typically the backsheetside) is placed toward the T-rod 1101.

The T-rod 1101 is "zeroed" on top of the sample 1000 with a lightpreload of a few grams (1 to 4 grams_(f)). This takes out any bowing ofthe sample and insures good contact of the T-rod with the sample. Eachsample is run through the 6 mm travel cycle twice, with a 30 second stopbetween cycles. A total of ten samples are run.

A graph of T-bar deflection force (grams_(f)) versus T-bar deflectiondistance (mm) will be generated. A representative run of a sampleshowing the two cycles is shown in FIG. 12. The deflection force at 4 mmand 5 mm,for each cycle, is determined on the recovery force curve. Therecovery deflection force at 4 mm and 5 mm are averaged to calculate acycle recovery deflection force. The average of both cycle recoverydeflection forces for each sample determines the sample recoverydeflection force. The bending flexure recovery force for the structureis the average of thevalue of the sample recovery deflection force forthe 10 samples.

EDGE COMPRESSION STIFFNESS TEST

The edge compression stiffness test uses an INSTRON Model 4502 asavailablefrom Instron Corporation of Canton, Mass., a special testsample holder, and mounting adhesive. As shown in FIG. 13, the samples1002 are mounted to a 1 inch (25 mm) by 2 inch (50 mm) by 1/16 inch(1.56 mm) aluminum flatplate 1300 by the mounting adhesive 1302. Themounting adhesive 1302 is a quick set epoxy as available from HartmanAdhesives of Belleville, N.J. and marketed as Red-04001 double bubblepacks.

The INSTRON is provided with a compression load cell. (The load cell andthe INSTRON jaw flat plate should be checked for flatness andsquareness.)The INSTRON is set for a crosshead speed of 5 mm/min., achart speed of 250mm/min., and full scale of 100 or 500 grams (asneeded). The cycle length is 3.5 mm down and back, with the chart tofollow the crosshead unit down and back.

As shown in FIG. 10, the sample 1002 to be tested is taken from theelasticwaist feature 34 in preferably the waistline panel zone 138 orthe shaping panel zone 136 or the interconnecting panel zone 130depending upon which zone is to be tested. The sample 1002 is 9 mm inlength by 25 mm wide.

The mounting adhesive 1302 is spaced on the plate 1300 using a doctorbladeto make a footprint approximately 3/8 inch (8.5 mm) wide and aheight of 0.020 inch to about 0.030 inch (0.5 to 0.75 mm). The sample1002 is placedin the mounting adhesive 1302 and held perpendicular tothe plate 1300 withblocks on either side of the sample. These blocks arerelieved at the base so that they will not get into the mountingadhesive. After the mounting adhesive has been given some time to set(approximately 3 minute or more),the mounted samples are placed in a73°F./50% relative humidity roomfor about 24 hours or overnight so thatthe mounting adhesive can fully set.

The mounted samples are placed on the lower jaw 1400 of the INSTRON asshown in FIG. 14. The samples are preloaded with a 1 to 4 grams_(f)preload to zero the INSTRON. Each sample is run through a 3.0 mmdeflection cycle twice, with 30 seconds allowed between the cycles. Fivesamples are tested.

A graph of compression force (grams_(f)) versus compression displacement(mm) will be generated. A representation run of a sample showing the twocycles is shown in FIG. 15. The peak force for the run is measured asthe highest force generated during both cycles. The average of the peakcompression forces for the five samples is the edge compressionstiffness of the zone.

EXTENSION FORCE TEST

The extension force test for both the elasticized side panels 30 and theelasticized waistband 35 uses an INSTRON Model 4502 as available fromInstron Corporation of Canton, Mass.

A. ELASTICIZED SIDE PANELS

The INSTRON is set for a crosshead speed of 100 mm/min, a chart speed of500 mm/min and with full scale at 1000 grams_(f). The INSTRON will beallowed to travel the desired, claimed, or full elastic extension of theside panel. If the full extension of the side panel is less than theupperlimit claimed, then the test is stopped at this extension since theextension forces at nonextensible areas should not be taken intoaccount; i.e., the designed in-use extension limit has been reached.)

The sample to be tested is determined on the actual diaper itself. Astandard 3 inch (75 mm) clamp is attached to the elasticized side panel30adjacent the edge of the activated stretch portion of the side panellaterally closest to the longitudinal centerline 67. In most situations,this edge corresponds to the side edge 91 of the elastic side panelmember90. A standard 1 inch (25 mm) clamp is attached to the oppositeedge of theactivated stretch portion of the elasticized side panel 30(typically the side edge 91' of the elastic side panel member 90). The 1inch clamp is positioned so as to be within the area of the 3 inch clampand longitudinally aligned with the component of the primary fasteningsystem 38 positioned adjacent the elasticized side panel 30. Thus, in apreferredembodiment, the 1 inch clamp is longitudinally aligned with thesecurement member 42, tape tab 92, so that the force applied by theINSTRON is similar to the force applied by the user when applying thediaper.

Each sample is run through a travel cycle to the designed, claimed, orfullextension of the activated elastic portion of the elasticized sidepanel. (The sample may be allowed to contract to also measurecontractive force.)A graph of extension force (grams_(f)) versusextension (mm) will be generated. A total of ten samples are run. Theextension force at a given extension is the average of the values forthe 10 samples.

B. ELASTICIZED WAISTBAND

The INSTRON is set for a crosshead speed of 500 mm/min, a chart speed of500 mm/min, and with full scale at 500 grams_(f). The INSTRON will beallowed to travel the desired, claimed, or full elastic extension of thewaistband. (If the full extension of the waistband is less than theupper limit claimed, then the test is stopped at this extension sincethe extension forces at nonextensible areas should not be taken intoaccount; i.e., the designed in-use extension limit has been reached.)The sample tobe tested is taken from the elasticized waistband 35,preferably adjacent the upper edge of the elasticized waistband (exceptwhere specific panel zones are to be tested). The sample is preferably25 mm (1 inch) long (longitudinal direction) and about 125 mm to about150 mm wide (lateral direction) so that a sample width of 100 mm (4inches) is tested. If the elasticized waistband 35 or the panel zone tobe tested is less than 25 mm(1 inch) long (longitudinal direction) sothat a 25 mm (1 inch) sample cannot be obtained, the test may be carriedout using this modified size sample although this is not a preferredsituation. The ends of the sample are clamped using standard 1 inch (25mm) clamps with 4 inches (100 mm) between the clamps. (No zones or areasof the sample should be nonextensible excluding bond sites).

Each sample is run through a travel cycle to the desired, claimed, orfull extension of the elasticized waistband sample. (The sample may beallowed to contract to also measure contractive force.) A graph ofextension force(grams_(f)) versus extension (mm) will be generated. Atotal of ten samples are run. The extension force at a given extensionis the average of the values for the 10 samples.

While particular embodiments of the present invention have beenillustratedand described, it would be obvious to those skilled in theart that variousother changes and modifications can be made withoutdeparting from the spirit and scope of the invention. It is thereforeintended to cover in the appended claims all such changes andmodifications that are within thescope of this invention.

What is claimed is:
 1. A disposable absorbent article comprising:a liquid pervious topsheet; a liquid impervious backsheet joined with said topsheet; an absorbent core having side edges and waist edges, said absorbent core being positioned between said topsheet and said backsheet; and an elastic feature extending outwardly from one of said edges of said absorbent core, said elastic feature comprising a segment of said backsheet which extends beyond said edge of said absorbent core and an elastomeric member joined with said backsheet such that a portion of said backsheet segment coincides with at least a portion of said elastomeric member, said portion of said backsheet coinciding with said elastic member being mechanically prestrained to permanently elongate portions of said backsheet prior to combining said backsheet with said elastomeric member.
 2. The absorbent article of claim 1 wherein said elastic feature comprises an elastic waist feature at least extending longitudinally outwardly from one of said waist edges of said absorbent core, said elastic waist feature comprising an elasticized waistband, said elasticized waistband comprising said elastomeric member and said segment of said backsheet which extends beyond the waist edge of said absorbent core.
 3. The absorbent article of claim 2 wherein said elasticized waistband additionally comprises a segment of said topsheet which extends beyond said waist edge of said absorbent core.
 4. The absorbent article of claim 3 wherein said elastomeric member is positioned between said backsheet and said topsheet.
 5. The absorbent article of claim 4 wherein said elasticized waistband additionally comprises a resilient member positioned between said backsheet and said elastomeric member.
 6. The absorbent article of claim 3 wherein said elasticized waistband additionally comprises a facing member, said elastomeric member being positioned between said backsheet and said facing member, and said topsheet being positioned between said backsheet and said elastomeric member.
 7. The absorbent article of claim 6 wherein said elasticized waistband additionally comprises a resilient member positioned between said topsheet and said elastomeric member.
 8. The absorbent article of claim 2 wherein said mechanically prestrained portion of said backsheet comprises a pattern of ribs and unstrained gaps between each rib.
 9. The absorbent article of claim 8 wherein said ribs are about 0.25 inches long, 0.03 inches wide, and 0.125 inches deep, and wherein the unstrained gaps between each rib is about 0.1 inches.
 10. The absorbent article of claim 9 wherein the area of said backsheet which is mechanically prestrained is about 5.5 inches wide by 1 inch long.
 11. The absorbent article of claim 2 wherein said elasticized waistband is a zero strain stretch laminate.
 12. The absorbent article of claim 1, 2, or 4 wherein said elastomeric member comprises a heat shrinkable elastic material.
 13. The absorbent article of claim 5 or 7 wherein said elastomeric member comprises a heat shrinkable elastic material, and said resilient member comprises a nonwoven fibrous web.
 14. The absorbent article of claim 2 additionally comprising elasticized side panels, each of said elasticized side panels being elastically extensible in the lateral direction. 